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Conserved domains on  [gi|442796478|gb|AGC74165|]
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spike protein [Bat coronavirus Rp/Shaanxi2011]

Protein Classification

Graphical summary

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List of domain hits

Name Accession Description Interval E-value
SARS-CoV-like_Spike_SD1-2_S1-S2_S2 cd22378
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
514-1175 0e+00

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from SARS-CoV-2 (COVID-19) and related betacoronaviruses in the B lineage; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses in the sarbecovirus subgenus (B lineage), including highly pathogenic human CoVs such as Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), and SARS-CoV-2 (also known as a 2019 novel coronavirus or 2019-nCoV). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. Notably, SARS-CoV-2 has a functional polybasic (furin) cleavage site through the insertion of PRRAR*SV (* indicates the cleavage site) at the S1/S2 interface, which is absent in SARS-CoV and other SARS-related coronaviruses. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


:

Pssm-ID: 411965 [Multi-domain]  Cd Length: 662  Bit Score: 1408.98  E-value: 0e+00
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  514 FNGLKGTGVLTASSKKFQSFQQFGRDASDFTDSVRDPQTLEILDISPCSFGGVSVITPGTNASTEVAVLYQDVNCTDVPT 593
Cdd:cd22378     1 FNGLTGTGVLTPSSKRFQPFQQFGRDVSDFTDSVRDPKTLEILDISPCSFGGVSVITPGTNASSEVAVLYQDVNCTDVPT 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  594 AINADQLTPAWRVYSTGINVFQTQAGCLIGAEHVNASYECDIPIGAGICASYHTASVLRSTGQKSIVAYTMSLGAENSIA 673
Cdd:cd22378    81 AIHADQLTPAWRVYSTGSNVFQTQAGCLIGAEHVNTSYECDIPIGAGICASYHTVSLLRSTSQKSIVAYTMSLGAENSIA 160
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  674 YANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVK 753
Cdd:cd22378   161 YSNNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSTECSNLLLQYGSFCTQLNRALSGIAVEQDKNTQEVFAQVK 240
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  754 QMYKTPAIKDFGGFNFSQILPDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGECLGDISARDLICAQKFNGLTVLPPLLT 833
Cdd:cd22378   241 QMYKTPTIKDFGGFNFSQILPDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGDCLGDINARDLICAQKFNGLTVLPPLLT 320
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  834 DEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALG 913
Cdd:cd22378   321 DEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALG 400
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  914 KLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAA 993
Cdd:cd22378   401 KLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAA 480
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  994 TKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFPREGVFVSNGTSWFITQ 1073
Cdd:cd22378   481 TKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFPREGVFVSNGTSWFITQ 560
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1074 RNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGDISGINASVVNIQKEIDRL 1153
Cdd:cd22378   561 RNFYSPQIITTDNTFVSGNCDVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGDISGINASVVNIQKEIDRL 640
                         650       660
                  ....*....|....*....|..
gi 442796478 1154 NEVAKNLNESLIDLQELGKYEQ 1175
Cdd:cd22378   641 NEVAKNLNESLIDLQELGKYEQ 662
SARS-CoV-like_Spike_S1_NTD cd21624
N-terminal domain of the S1 subunit of the Spike (S) protein from Severe acute respiratory ...
15-294 1.98e-174

N-terminal domain of the S1 subunit of the Spike (S) protein from Severe acute respiratory syndrome coronavirus and related betacoronaviruses in the B lineage; This subfamily contains the N-terminal domain (NTD) of the S1 subunit of the Spike (S) proteins from betacoronaviruses in the sarbecovirus subgenera (B lineage), including the highly pathogenic human coronavirus (CoV), Severe acute respiratory syndrome (SARS) CoV, and SARS-CoV-2, also known as a 2019 novel coronavirus (2019-nCoV) or COVID-19 virus. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). Most CoVs, including SARS-CoV-2 and SARS-CoV, use the C-domain to bind their receptors. The S1 NTD contributes to the Spike trimer interface.


:

Pssm-ID: 394950  Cd Length: 280  Bit Score: 515.73  E-value: 1.98e-174
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   15 EGCGVISNKPQRTFDQYSSTFRGVYYNDDIFRSDVLHLTQDYFLPFNTNVTRYLSLNAAQNTIVYFDNHVIPFYDGIYFA 94
Cdd:cd21624     1 EGCTTFSDKTAPNMTQYSSSRRGVYYPDDIFRSDVLVLTQDYFLPFNSNVTWYHSLNALGERKYYFDNPVLPFGDGVYFA 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   95 ATERSNVIRGWIFGSTFDNRSQSAIIVNNSTHILVKVCNFVLCTEPMFTVSR-NQHYKSWVYQHARNCTYDVAYPSFQLD 173
Cdd:cd21624    81 ATEKSNVVRGWIFGSTFDNTSQSAIIVNNGTHIIIRVCNFQLCKNPMFAVSKpGTQTNSWIYSNAFNCTYEYVSQSFQLD 160
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  174 VSLKnNVNFQHLREFIFKNVDGFLKIYSSYEPINVVSGIPSGFSVLKPVMSLPLGINITGMRVVMTMFSNTQANFLTENA 253
Cdd:cd21624   161 VSEK-NGNFKHLREFVFKNVDGFLKVYHGYQPINVVRGLPSGFSVLKPIFKLPLGINITNFRVVLTMFSPAQSNWTAGNA 239
                         250       260       270       280
                  ....*....|....*....|....*....|....*....|.
gi 442796478  254 AYYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKCTLK 294
Cdd:cd21624   240 AYYVGYLKPTTFMLKFDENGTITDAVDCSQDPLAELKCTLK 280
SARS-CoV-like_Spike_S1_RBD cd21477
receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related ...
309-512 7.39e-146

receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related coronavirus Spike (S) protein and similar proteins; This subfamily contains the receptor-binding domain of the S1 subunit of coronavirus (CoV) spike (S) proteins from highly pathogenic human virus, severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), SARS coronavirus 2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV), and other SARS-like coronaviruses. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2 and SARS-CoV use the C-domain to bind their receptors. Recent studies found that the receptor-binding domain (RBD) of SARS-CoV-2 S protein binds strongly to human and bat angiotensin-converting enzyme 2 (ACE2) receptors. Moreover, SARS-CoV-2 RBD exhibited significantly higher binding affinity to the ACE2 receptor than SARS-CoV RBD. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for SARS-CoV, SARS-CoV-2, and most CoVs.


:

Pssm-ID: 394824  Cd Length: 205  Bit Score: 438.10  E-value: 7.39e-146
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  309 RVSPTQEVVRFPNITNRCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 388
Cdd:cd21477     1 RVSPTTEVVRFPNITNLCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  389 TFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWNTANQDQGQYYYRSSRKEKLKPFERDLSSDEN-GVYTLSTYD 467
Cdd:cd21477    81 TFLIRGSEVRQVAPGQTGVIADYNYKLPDDFTGCVIAWNTAKQDNGNYYYRSHRKSKLKPFERDLSSDENsGVRTLSTYD 160
                         170       180       190       200
                  ....*....|....*....|....*....|....*....|....*
gi 442796478  468 FYPSVPLDYQATRVVVLSFELLNAPATVCGPKLSTTLVKNQCVNF 512
Cdd:cd21477   161 FNPTVPVGYQATRVVVLSFELLNAPATVCGPKLSTELVKNQCVNF 205
CoV_S2_C pfam19214
Coronavirus spike glycoprotein S2, intravirion; This entry represents the cysteine rich ...
1200-1239 2.19e-05

Coronavirus spike glycoprotein S2, intravirion; This entry represents the cysteine rich intravirion region found at the C-terminus of coronavirus spike proteins (S). These cysteine residues are targets for palmitoylation, necessary for efficiently S incorporation into virions and S-mediated membrane fusions.


:

Pssm-ID: 465998  Cd Length: 42  Bit Score: 42.79  E-value: 2.19e-05
                           10        20        30        40
                   ....*....|....*....|....*....|....*....|..
gi 442796478  1200 LLCCMTSCCSCLKGaCSCGSCC-KFDE-DDSEPVLKGVKLHY 1239
Cdd:pfam19214    1 FCCCCTGCCGCCFG-CSCGGCCdSYDKrDDVYPAEVVEKVHV 41
 
Name Accession Description Interval E-value
SARS-CoV-like_Spike_SD1-2_S1-S2_S2 cd22378
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
514-1175 0e+00

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from SARS-CoV-2 (COVID-19) and related betacoronaviruses in the B lineage; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses in the sarbecovirus subgenus (B lineage), including highly pathogenic human CoVs such as Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), and SARS-CoV-2 (also known as a 2019 novel coronavirus or 2019-nCoV). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. Notably, SARS-CoV-2 has a functional polybasic (furin) cleavage site through the insertion of PRRAR*SV (* indicates the cleavage site) at the S1/S2 interface, which is absent in SARS-CoV and other SARS-related coronaviruses. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411965 [Multi-domain]  Cd Length: 662  Bit Score: 1408.98  E-value: 0e+00
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  514 FNGLKGTGVLTASSKKFQSFQQFGRDASDFTDSVRDPQTLEILDISPCSFGGVSVITPGTNASTEVAVLYQDVNCTDVPT 593
Cdd:cd22378     1 FNGLTGTGVLTPSSKRFQPFQQFGRDVSDFTDSVRDPKTLEILDISPCSFGGVSVITPGTNASSEVAVLYQDVNCTDVPT 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  594 AINADQLTPAWRVYSTGINVFQTQAGCLIGAEHVNASYECDIPIGAGICASYHTASVLRSTGQKSIVAYTMSLGAENSIA 673
Cdd:cd22378    81 AIHADQLTPAWRVYSTGSNVFQTQAGCLIGAEHVNTSYECDIPIGAGICASYHTVSLLRSTSQKSIVAYTMSLGAENSIA 160
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  674 YANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVK 753
Cdd:cd22378   161 YSNNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSTECSNLLLQYGSFCTQLNRALSGIAVEQDKNTQEVFAQVK 240
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  754 QMYKTPAIKDFGGFNFSQILPDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGECLGDISARDLICAQKFNGLTVLPPLLT 833
Cdd:cd22378   241 QMYKTPTIKDFGGFNFSQILPDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGDCLGDINARDLICAQKFNGLTVLPPLLT 320
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  834 DEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALG 913
Cdd:cd22378   321 DEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALG 400
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  914 KLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAA 993
Cdd:cd22378   401 KLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAA 480
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  994 TKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFPREGVFVSNGTSWFITQ 1073
Cdd:cd22378   481 TKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFPREGVFVSNGTSWFITQ 560
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1074 RNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGDISGINASVVNIQKEIDRL 1153
Cdd:cd22378   561 RNFYSPQIITTDNTFVSGNCDVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGDISGINASVVNIQKEIDRL 640
                         650       660
                  ....*....|....*....|..
gi 442796478 1154 NEVAKNLNESLIDLQELGKYEQ 1175
Cdd:cd22378   641 NEVAKNLNESLIDLQELGKYEQ 662
CoV_S2 pfam01601
Coronavirus spike glycoprotein S2; The coronavirus spike glycoprotein forms the characteriztic ...
677-1178 0e+00

Coronavirus spike glycoprotein S2; The coronavirus spike glycoprotein forms the characteriztic 'corona' after which the group is named. The Spike glycoprotein is translated as a large polypeptide that is subsequently cleaved to S1 pfam01600 and S2,. The S2 subunit normally contains multiple key components, including one or more fusion peptides (FP), a second proteolytic site (S2') and two conserved heptad repeats (HRs), driving membrane penetration and virus-cell fusion. The HRs can trimerize into a coiled-coil structure built of three HR1-HR2 helical hairpins presenting as a canonical six-helix bundle and drag the virus envelope and the host cell bilayer into close proximity, preparing for fusion to occur.


Pssm-ID: 460263  Cd Length: 502  Bit Score: 668.59  E-value: 0e+00
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   677 NSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVKQMY 756
Cdd:pfam01601    1 GNISIPTNFTISVQTEYIQTTSPKVSVDCAQYVCNGNERCLQLLVQYGSFCSTIEQALQGSARLEDVEVLSMLSISNRAL 80
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   757 KTPAIKDFGG-FNFSQILPDPskPTKRSFIEDLLFNKVTLADAGFMKQYGECLGDISARDLICAQKFNGLTVLPPLLTDE 835
Cdd:pfam01601   81 TLATISNFGSdFNFSSFLPCL--NSGRSAIEDLLFDKVVTSGLGTVDAYKKCTKGTSIADLVCAQYYNGIMVLPGVVDAE 158
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   836 MIAAYTAALVSGTATAGWTFGAGAalqIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALGKL 915
Cdd:pfam01601  159 KMAMYTASLTGGMAFGGLTGAAAA---IPFALAVQARLNYLGLQTDVLQENQKILANAFNNAVGNITDGFTTTASALSKI 235
                          250       260       270       280       290       300       310       320
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   916 QDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATK 995
Cdd:pfam01601  236 QDVVNANAQALNQLTQQLSNNFGAISSSIQDIYSRLDQLEADAQVDRLINGRLAALNAFVTQQLTKASEVKASRQLAQQK 315
                          330       340       350       360       370       380       390       400
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   996 MSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGK-AYFPREGVFVSNGTS-WFITQ 1073
Cdd:pfam01601  316 VNECVKSQSSRYGFCGNGTHLFSLPQAAPNGIMFLHTVLVPTEYITVKATPGLCVNGTtGYAPRDGQFVLNNTSnWYITP 395
                          410       420       430       440       450       460       470       480
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  1074 RNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLgDISGINASVVNIQKEI--- 1150
Cdd:pfam01601  396 RNMYQPRPITGSDFVQISSCDVNFVNITNTKLPPLIPDYVDFNKELEDIYKNLNSTLPDL-DLDIFNATILNLTDEIkdl 474
                          490       500
                   ....*....|....*....|....*...
gi 442796478  1151 DRLNEVAKNLNESLIDLQELGKYEQYIK 1178
Cdd:pfam01601  475 ERLQELIDNLNQTLVDLEWLNRYETYIK 502
SARS-CoV-like_Spike_S1_NTD cd21624
N-terminal domain of the S1 subunit of the Spike (S) protein from Severe acute respiratory ...
15-294 1.98e-174

N-terminal domain of the S1 subunit of the Spike (S) protein from Severe acute respiratory syndrome coronavirus and related betacoronaviruses in the B lineage; This subfamily contains the N-terminal domain (NTD) of the S1 subunit of the Spike (S) proteins from betacoronaviruses in the sarbecovirus subgenera (B lineage), including the highly pathogenic human coronavirus (CoV), Severe acute respiratory syndrome (SARS) CoV, and SARS-CoV-2, also known as a 2019 novel coronavirus (2019-nCoV) or COVID-19 virus. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). Most CoVs, including SARS-CoV-2 and SARS-CoV, use the C-domain to bind their receptors. The S1 NTD contributes to the Spike trimer interface.


Pssm-ID: 394950  Cd Length: 280  Bit Score: 515.73  E-value: 1.98e-174
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   15 EGCGVISNKPQRTFDQYSSTFRGVYYNDDIFRSDVLHLTQDYFLPFNTNVTRYLSLNAAQNTIVYFDNHVIPFYDGIYFA 94
Cdd:cd21624     1 EGCTTFSDKTAPNMTQYSSSRRGVYYPDDIFRSDVLVLTQDYFLPFNSNVTWYHSLNALGERKYYFDNPVLPFGDGVYFA 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   95 ATERSNVIRGWIFGSTFDNRSQSAIIVNNSTHILVKVCNFVLCTEPMFTVSR-NQHYKSWVYQHARNCTYDVAYPSFQLD 173
Cdd:cd21624    81 ATEKSNVVRGWIFGSTFDNTSQSAIIVNNGTHIIIRVCNFQLCKNPMFAVSKpGTQTNSWIYSNAFNCTYEYVSQSFQLD 160
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  174 VSLKnNVNFQHLREFIFKNVDGFLKIYSSYEPINVVSGIPSGFSVLKPVMSLPLGINITGMRVVMTMFSNTQANFLTENA 253
Cdd:cd21624   161 VSEK-NGNFKHLREFVFKNVDGFLKVYHGYQPINVVRGLPSGFSVLKPIFKLPLGINITNFRVVLTMFSPAQSNWTAGNA 239
                         250       260       270       280
                  ....*....|....*....|....*....|....*....|.
gi 442796478  254 AYYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKCTLK 294
Cdd:cd21624   240 AYYVGYLKPTTFMLKFDENGTITDAVDCSQDPLAELKCTLK 280
SARS-CoV-like_Spike_S1_RBD cd21477
receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related ...
309-512 7.39e-146

receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related coronavirus Spike (S) protein and similar proteins; This subfamily contains the receptor-binding domain of the S1 subunit of coronavirus (CoV) spike (S) proteins from highly pathogenic human virus, severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), SARS coronavirus 2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV), and other SARS-like coronaviruses. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2 and SARS-CoV use the C-domain to bind their receptors. Recent studies found that the receptor-binding domain (RBD) of SARS-CoV-2 S protein binds strongly to human and bat angiotensin-converting enzyme 2 (ACE2) receptors. Moreover, SARS-CoV-2 RBD exhibited significantly higher binding affinity to the ACE2 receptor than SARS-CoV RBD. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for SARS-CoV, SARS-CoV-2, and most CoVs.


Pssm-ID: 394824  Cd Length: 205  Bit Score: 438.10  E-value: 7.39e-146
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  309 RVSPTQEVVRFPNITNRCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 388
Cdd:cd21477     1 RVSPTTEVVRFPNITNLCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  389 TFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWNTANQDQGQYYYRSSRKEKLKPFERDLSSDEN-GVYTLSTYD 467
Cdd:cd21477    81 TFLIRGSEVRQVAPGQTGVIADYNYKLPDDFTGCVIAWNTAKQDNGNYYYRSHRKSKLKPFERDLSSDENsGVRTLSTYD 160
                         170       180       190       200
                  ....*....|....*....|....*....|....*....|....*
gi 442796478  468 FYPSVPLDYQATRVVVLSFELLNAPATVCGPKLSTTLVKNQCVNF 512
Cdd:cd21477   161 FNPTVPVGYQATRVVVLSFELLNAPATVCGPKLSTELVKNQCVNF 205
bCoV_S1_N pfam16451
Betacoronavirus-like spike glycoprotein S1, N-terminal; This entry represents the N-terminal ...
31-324 9.15e-95

Betacoronavirus-like spike glycoprotein S1, N-terminal; This entry represents the N-terminal domain of the betacoronavirus-like trimeric spike glycoprotein. The distal S1 subunit of the coronavirus spike protein is responsible for receptor binding. S1 contains two domains; an N-terminal galectin-like domain (NTD) and a receptor-binding domain (S1 RBD) also referred to as the S1 CTD or domain B. Either the S1 NTD or S1 RBD, or occasionally both, are involved in binding to host receptors. S1 NTD is located on the side of the spike trimer and mainly recognizes sugar receptors. For many betacoronaviruses (b-CoVs), for example mouse hepatitis virus (MHV), the RBD is located in the NTD. The structure of the MHV S1 NTD showed the same fold as human galectins (galactose-binding lectin), however it does not bind any sugar; instead, it binds to the carcinoembryonic antigen cell-adhesion molecule CEACAM1) through protein-protein interactions. All three CEACAM21a-binding sites in MHV spikes can be fully occupied by CEACAM1a. It has been shown that CEACAM1a binding to the MHV spike weakens the interactions between S1 and S2 and facilitates the proteolysis of the spike protein and dissociation of S1. The homologous bovine CoV (BCov) S1 NTD also possesses a galectin fold but binds to sialic acid-containing moieties on host cell membranes, as does the NTD of three other group A b-Covs, namely human CoV (HCoV) OC43, avian b-CoV, and infectious bronchitis virus (IBV). Despite the S1 NTD of human respiratory b-CoV HKU1 being highly homologous to the NTDs of MHV and bovine CoV, it does not bind to either sugar or human carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) and the RBD is found instead in the S1 RBD domain.


Pssm-ID: 465119  Cd Length: 296  Bit Score: 305.49  E-value: 9.15e-95
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478    31 YSSTFRGVYY-NDDIFrSDVLHLTQDYFLPFNTNVTRYLSLNAAQNTIVYFDNHVIPFYDGIYFAATERSNVIRG----- 104
Cdd:pfam16451    1 DVSKADGTYYlPDRVY-SNTTTLRQGLFPKQGDNVTNYVYSPAHHCGKRNFSTPFLPFGDGIFVHIGNASNATGGriise 79
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   105 ---WIFGSTFDNRSQSAIIVNNS--THILVKVCNFVLCTEPMFTVS----RNQHYKSWVYQ-HARNCTYDVAYpSFQLDV 174
Cdd:pfam16451   80 ppaFVFGSTFGNTSHTLIIAPDScqTNLTILVCNFTLCANPVTACRwgagNYNANNSLVYFkNAINCTFNRTY-NITFDT 158
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   175 SLknnvnfqhlREFIFKNVDGFLKIYSSYEPInvvsGIPSGFSVLKPVMSLPLGINITGMRVVMTMFSNTQaNFLTENAA 254
Cdd:pfam16451  159 SL---------IYFGFKQQDGGFHIYYSYWLP----DLDSGPPTLFPFATLPLGINITYFQVIPSSIRSTQ-NCRRANAA 224
                          250       260       270       280       290       300       310
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 442796478   255 YYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKCTLKNFNITKGIYQTSNFRVSPTQEVV-RFPNITN 324
Cdd:pfam16451  225 YYVAPLKPSTFLLDFDVNGYITNAVDCSFDPLSELKCSTGSFEPDTGVYSTSSYRAQPVGSVYvRQPNVTC 295
bCoV_S1_RBD pfam09408
Betacoronavirus spike glycoprotein S1, receptor binding; This entry represents the receptor ...
338-497 2.40e-40

Betacoronavirus spike glycoprotein S1, receptor binding; This entry represents the receptor binding domain (S1 RBD) of the betacoronavirus spike glycoprotein. The spike glycoprotein is arranged in trimers on the surface of the viral membrane and is essential for viral entry. The spike protein is translated as a large polypeptide that is subsequently cleaved to the distal S1, responsible for receptor binding, and the membrane-anchored S2 responsible for membrane fusion. The coronavirus (SARS-CoV) S1 subunit is composed of two distinct domains: an N-terminal domain (S1 NTD) and a receptor-binding domain (S1 RBD) also referred to as the S1 CTD or domain B. Each of these domains have been implicated in binding to host receptors. However, most coronaviruses are not known to utilize both the S1 NTD and S1 RBD for viral entry. SARS-CoV makes use of its S1 RBD to bind to the human angiotensin-converting enzyme 2 (ACE2) as its host receptor.


Pssm-ID: 462789  Cd Length: 156  Bit Score: 146.49  E-value: 2.40e-40
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   338 PSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYADTFLIRSSEVRQVAPGETGVIADYNYKLPD 417
Cdd:pfam09408    1 PSPANWERKTFSNCNFDFSVLLSLLQVSSFKCYGVSPSKLADMCYGSVTIDYFAIPETHKSNLQPGSPGAISKYNYKLPD 80
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   418 DFTGCVIAWNTANQDQ----GQYYYRSSRKEKLKPFERDLSSDENgvytlsTYDFYPSVPLDYQAtrVVVLSFELLNAPA 493
Cdd:pfam09408   81 DFYGCVLAFNVNANTNyafaDNYPYRYIKPGQYQPCNSFVSTVPN------SPDGHYCTPSSFNG--VVVITLKPATGSN 152

                   ....
gi 442796478   494 TVCG 497
Cdd:pfam09408  153 LVCP 156
CoV_S2_C pfam19214
Coronavirus spike glycoprotein S2, intravirion; This entry represents the cysteine rich ...
1200-1239 2.19e-05

Coronavirus spike glycoprotein S2, intravirion; This entry represents the cysteine rich intravirion region found at the C-terminus of coronavirus spike proteins (S). These cysteine residues are targets for palmitoylation, necessary for efficiently S incorporation into virions and S-mediated membrane fusions.


Pssm-ID: 465998  Cd Length: 42  Bit Score: 42.79  E-value: 2.19e-05
                           10        20        30        40
                   ....*....|....*....|....*....|....*....|..
gi 442796478  1200 LLCCMTSCCSCLKGaCSCGSCC-KFDE-DDSEPVLKGVKLHY 1239
Cdd:pfam19214    1 FCCCCTGCCGCCFG-CSCGGCCdSYDKrDDVYPAEVVEKVHV 41
 
Name Accession Description Interval E-value
SARS-CoV-like_Spike_SD1-2_S1-S2_S2 cd22378
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
514-1175 0e+00

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from SARS-CoV-2 (COVID-19) and related betacoronaviruses in the B lineage; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses in the sarbecovirus subgenus (B lineage), including highly pathogenic human CoVs such as Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), and SARS-CoV-2 (also known as a 2019 novel coronavirus or 2019-nCoV). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. Notably, SARS-CoV-2 has a functional polybasic (furin) cleavage site through the insertion of PRRAR*SV (* indicates the cleavage site) at the S1/S2 interface, which is absent in SARS-CoV and other SARS-related coronaviruses. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411965 [Multi-domain]  Cd Length: 662  Bit Score: 1408.98  E-value: 0e+00
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  514 FNGLKGTGVLTASSKKFQSFQQFGRDASDFTDSVRDPQTLEILDISPCSFGGVSVITPGTNASTEVAVLYQDVNCTDVPT 593
Cdd:cd22378     1 FNGLTGTGVLTPSSKRFQPFQQFGRDVSDFTDSVRDPKTLEILDISPCSFGGVSVITPGTNASSEVAVLYQDVNCTDVPT 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  594 AINADQLTPAWRVYSTGINVFQTQAGCLIGAEHVNASYECDIPIGAGICASYHTASVLRSTGQKSIVAYTMSLGAENSIA 673
Cdd:cd22378    81 AIHADQLTPAWRVYSTGSNVFQTQAGCLIGAEHVNTSYECDIPIGAGICASYHTVSLLRSTSQKSIVAYTMSLGAENSIA 160
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  674 YANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVK 753
Cdd:cd22378   161 YSNNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSTECSNLLLQYGSFCTQLNRALSGIAVEQDKNTQEVFAQVK 240
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  754 QMYKTPAIKDFGGFNFSQILPDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGECLGDISARDLICAQKFNGLTVLPPLLT 833
Cdd:cd22378   241 QMYKTPTIKDFGGFNFSQILPDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGDCLGDINARDLICAQKFNGLTVLPPLLT 320
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  834 DEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALG 913
Cdd:cd22378   321 DEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALG 400
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  914 KLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAA 993
Cdd:cd22378   401 KLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAA 480
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  994 TKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFPREGVFVSNGTSWFITQ 1073
Cdd:cd22378   481 TKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFPREGVFVSNGTSWFITQ 560
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1074 RNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGDISGINASVVNIQKEIDRL 1153
Cdd:cd22378   561 RNFYSPQIITTDNTFVSGNCDVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGDISGINASVVNIQKEIDRL 640
                         650       660
                  ....*....|....*....|..
gi 442796478 1154 NEVAKNLNESLIDLQELGKYEQ 1175
Cdd:cd22378   641 NEVAKNLNESLIDLQELGKYEQ 662
betaCoV_Spike_SD1-2_S1-S2_S2 cd22370
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
514-1170 0e+00

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses; This family contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses, including three highly pathogenic human coronaviruses (CoVs), Middle East respiratory syndrome coronavirus (MERS-CoV), Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), and SARS coronavirus 2 (SARS-CoV-2), also known as a 2019 novel coronavirus (2019-nCoV). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HKU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Rousettus bat coronavirus HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411957 [Multi-domain]  Cd Length: 667  Bit Score: 1049.00  E-value: 0e+00
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  514 FNGLKGTGVLTASSKKFQSFQQFGRDASDFTDSVRDPQTLEILDISPCSFGGVSVITPGTNaSTEVAVLYQDVNCTDVPT 593
Cdd:cd22370     1 LYGYTGTGVLTETNATFLPFQNFGYDSNGNLIAFKDPQTNTIYTILPCVSGPVSVITPGNN-TNEVAVLYNGLNCSEVPS 79
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  594 AINADQLTPAWRVYSTGINVFQTQAGCLIGAE-HVNASYECDIPIGAGICASYHTASVL--RSTGQKSIVAYTMSLGAEN 670
Cdd:cd22370    80 AISAVSLTPWWRVYSSTSNYFDTPVGCLLGAVnSSNNSYECDLPLGAGLCASYTTQSVLrsRSVASRSIRLTTMSFFAEN 159
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  671 ----SIAYANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQ 746
Cdd:cd22370   160 svdvEVAYSNFSIQIPTNFTIAVTEEFIPTTMPKVTVDCAQYVCGDSSECSNLLLQYGTFCDNINRALTGVALLQDKNQL 239
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  747 EVFAQVKQMYKTPA-IKDFGGFNFSQILPDPS---KPTKRSFIEDLLFNKVTLADAGFMKQYGECLGDISARDLICAQKF 822
Cdd:cd22370   240 EVFASVKQIVKTPApLKDFGGFNFSSLLPCLGsngGSSARSAIEDLLFNKVTLADVGFMKQYDDCTGGSAARDLICAQSF 319
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  823 NGLTVLPPLLTDEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQ 902
Cdd:cd22370   320 NGLKVLPPLLTDEMIAAYTSALLGGTATSGWTFGASSAAQIPFAMQMAYRFNGIGVTQQVLVENQKLIANKFNQALGSIQ 399
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  903 ESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRA 982
Cdd:cd22370   400 TGFTATNSALAKLQDVVNQNAQALNTLVKQLSNNFGAISSSLNDILSRLDKLEADVQIDRLINGRLQVLQTYVTQQLIRA 479
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  983 AEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFPREGVF 1062
Cdd:cd22370   480 SEIRASAQLAAQKMSECVKGQSKRVDFCGNGTHLMSFPQSAPNGVVFLHVTYKPTSYKNVTTAPAICHNGKAYFPKEGVF 559
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1063 VSNGTSWFITQRNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGDISGINAS 1142
Cdd:cd22370   560 VKNNNSWMFTGRNFYEPEIITTDNTFYSGSCDVNFTYVNNTVYNPLQPELDDFKAELDKFFKNHTSPDPNLGDLSGINAS 639
                         650       660
                  ....*....|....*....|....*...
gi 442796478 1143 VVNIQKEIDRLNEVAKNLNESLIDLQEL 1170
Cdd:cd22370   640 FVDLQKEMDTLQEVVKQLNESLIDLKEL 667
CoV_Spike_S1-S2_S2 cd21698
S1/S2 cleavage region and the S2 fusion subunit of coronavirus spike (S) proteins; This model ...
638-1170 0e+00

S1/S2 cleavage region and the S2 fusion subunit of coronavirus spike (S) proteins; This model represents the S1/S2 cleavage region and the S2 subunit of the spike (S) glycoprotein from coronavirus (CoVs), including three highly pathogenic human CoVs, Middle East respiratory syndrome coronavirus (MERS-CoV), Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), and SARS coronavirus 2 (SARS-CoV-2), also known as a 2019 novel coronavirus (2019-nCoV). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect S1 and S2. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV, and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP), and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. Notably, SARS-CoV-2 has a functional polybasic (furin) cleavage site through the insertion of PRRAR*SV (* indicates the cleavage site) at the S1/S2 interface, which is absent in SARS-CoV and other SARS-related CoVs. The S1/S2 cleavage region and the S2 fusion subunit play an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411955 [Multi-domain]  Cd Length: 523  Bit Score: 718.43  E-value: 0e+00
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  638 GAGICASYhtasvlrstgqkSIVAYTMSLGAENS---IAYANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSL 714
Cdd:cd21698     1 YGGICICY------------DGAIYTVSTGQEESpsiVAISTENIAIPSNFTLSVTTEYLQVTMTKVSVDCTTYVCGGSP 68
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  715 ECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVKQMYKTPAIKDFGGFNFSQILPDPSKPTKRSFIEDLLFNKVT 794
Cdd:cd21698    69 RCKNLLLQYGSACDTIEQALRGIAVLEDSEVSNMFSTSKQALKLAIIKSFGGFNFSQILPTPSRPSGRSAIEDLLFTKVV 148
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  795 LADAGFMKQYGECLGDISARDLICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGwtfgAGAALQIPFAMQMAYRFN 874
Cdd:cd21698   149 TAGLGTVDQYKNCTKGIAIADLACAQYYNGIMVLPPVADAEKMAMYTGSLTAGMVFGG----ITAAAAIPFSLAMQARLN 224
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  875 GIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKV 954
Cdd:cd21698   225 YVGLQQNVLLENQKLLANSFNKAIGNISDAFSSTSSALQKIQDVVNQQAQALNTLTSQLSNNFGAISSSIQDIYQRLDKL 304
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  955 EAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTY 1034
Cdd:cd21698   305 EADVQVDRLITGRLAALNAFVTQQLIKAAEVRQSRRLAQQKINECVKSQSSRYGFCGNGTHLFSIPQSAPSGIVFLHTVL 384
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1035 VPSQERNFTTAPAICHEGKAYFPRE--GVFVSNGTSWFITQRNFYSPQIITTDNTFVAGSCNVVIGIINNTV-YDPLQPE 1111
Cdd:cd21698   385 VPTSYKNVTAYPGICVDGKAGSPLEgpLVFIQNNNHWFVTPRNMYEPRIITTADFVQITSCDANVTIVNNTVnLDPVIPD 464
                         490       500       510       520       530       540
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 442796478 1112 LDSFKEELDKYF---KNHTSPDVDLGdisGINASVVNIQKEIDRLNEVAKNLNESLIDLQEL 1170
Cdd:cd21698   465 YVDVNEELDDYIqnlPNHTLPDLDLS---GYNATILNISSEIDRLNEVAKNLNQSVVELQEY 523
CoV_S2 pfam01601
Coronavirus spike glycoprotein S2; The coronavirus spike glycoprotein forms the characteriztic ...
677-1178 0e+00

Coronavirus spike glycoprotein S2; The coronavirus spike glycoprotein forms the characteriztic 'corona' after which the group is named. The Spike glycoprotein is translated as a large polypeptide that is subsequently cleaved to S1 pfam01600 and S2,. The S2 subunit normally contains multiple key components, including one or more fusion peptides (FP), a second proteolytic site (S2') and two conserved heptad repeats (HRs), driving membrane penetration and virus-cell fusion. The HRs can trimerize into a coiled-coil structure built of three HR1-HR2 helical hairpins presenting as a canonical six-helix bundle and drag the virus envelope and the host cell bilayer into close proximity, preparing for fusion to occur.


Pssm-ID: 460263  Cd Length: 502  Bit Score: 668.59  E-value: 0e+00
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   677 NSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVKQMY 756
Cdd:pfam01601    1 GNISIPTNFTISVQTEYIQTTSPKVSVDCAQYVCNGNERCLQLLVQYGSFCSTIEQALQGSARLEDVEVLSMLSISNRAL 80
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   757 KTPAIKDFGG-FNFSQILPDPskPTKRSFIEDLLFNKVTLADAGFMKQYGECLGDISARDLICAQKFNGLTVLPPLLTDE 835
Cdd:pfam01601   81 TLATISNFGSdFNFSSFLPCL--NSGRSAIEDLLFDKVVTSGLGTVDAYKKCTKGTSIADLVCAQYYNGIMVLPGVVDAE 158
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   836 MIAAYTAALVSGTATAGWTFGAGAalqIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALGKL 915
Cdd:pfam01601  159 KMAMYTASLTGGMAFGGLTGAAAA---IPFALAVQARLNYLGLQTDVLQENQKILANAFNNAVGNITDGFTTTASALSKI 235
                          250       260       270       280       290       300       310       320
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   916 QDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATK 995
Cdd:pfam01601  236 QDVVNANAQALNQLTQQLSNNFGAISSSIQDIYSRLDQLEADAQVDRLINGRLAALNAFVTQQLTKASEVKASRQLAQQK 315
                          330       340       350       360       370       380       390       400
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   996 MSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGK-AYFPREGVFVSNGTS-WFITQ 1073
Cdd:pfam01601  316 VNECVKSQSSRYGFCGNGTHLFSLPQAAPNGIMFLHTVLVPTEYITVKATPGLCVNGTtGYAPRDGQFVLNNTSnWYITP 395
                          410       420       430       440       450       460       470       480
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  1074 RNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLgDISGINASVVNIQKEI--- 1150
Cdd:pfam01601  396 RNMYQPRPITGSDFVQISSCDVNFVNITNTKLPPLIPDYVDFNKELEDIYKNLNSTLPDL-DLDIFNATILNLTDEIkdl 474
                          490       500
                   ....*....|....*....|....*...
gi 442796478  1151 DRLNEVAKNLNESLIDLQELGKYEQYIK 1178
Cdd:pfam01601  475 ERLQELIDNLNQTLVDLEWLNRYETYIK 502
bat-HKU9-CoV-like_Spike_SD1-2_S1-S2_S2 cd22381
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
514-1233 0e+00

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from Rousettus bat coronavirus HKU9 and related betacoronaviruses in the D lineage; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses in the nobecovirus subgenus (D lineage), including Rousettus bat coronavirus HKU9 (Ro-BatCoV HKU9). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HCoV-KU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Ro-BatCoV HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411968 [Multi-domain]  Cd Length: 731  Bit Score: 624.09  E-value: 0e+00
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  514 FNGLKGTGVLTASSKKFQSFQQFGRDASDFTDSVRDPQTleILDISPCSFGGVSVitpGTNASTEVAVLYQDVNCTDVPT 593
Cdd:cd22381     1 LYGYTGTGVLSTSNLTIPDSKVFSASSTGDIIAVSVNGT--VYSISPCVSVPISV---GYDPGFERALLFNGLSCSERAR 75
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  594 AINaDQLTPAWR--VYSTGINVFQTQAGCLIGAEHVNASY--ECDIPIGAGICASYHTASVLRSTGQK--SIVAYTMSLG 667
Cdd:cd22381    76 AVS-EPASDYWRasVSDGANNTFDTPSGCVYNVINRTTITvnQCSMPLGNSLCLVNNTTAVSARGSLSllSLVTYDPLYD 154
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  668 AENSIAYANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQE 747
Cdd:cd22381   155 SSVTPLTPVYWVSIPTNFTLAATTEYIQTTAPKINIDCAKYLCGDSSRCLTVLLQYGTFCDDVNKALARVSTILDASLVS 234
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  748 VFAQVKQMYKTPAIKDFGG-FNFSQIL----PDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGECL-----GDIsaRDLI 817
Cdd:cd22381   235 LVSELTSDVVRSENLAFDGdYNFTGLMgclgSNCNSKSYRSALSDLLYNKVKVADPGFMQSYQKCIdsqwgGNI--RDLI 312
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  818 CAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGWTFGAGAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKA 897
Cdd:cd22381   313 CTQTFNGISVLPPIVSPGMQALYTSLLVGAVASSGYTFGITSVGVIPFATQLQFRLNGLGVTTQVLVENQKLIANSFNKA 392
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  898 ISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQ 977
Cdd:cd22381   393 LVSIQKGFDATNQALSKMQTVINQHAQQLQTLVQQLGNSFGAISSSINEIFSRLDGLEANAEVDRLINGRMVVLNTYVTQ 472
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  978 QLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYFP 1057
Cdd:cd22381   473 LLIQASEVRAQAALAKQKISECVKAQSLRNDFCGNGTHVLSIPQLAPNGVLFIHYSYQPTAYALVQTAAGLCFNGTGYAP 552
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1058 REGVFV--SNGTSWFITQRNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPELDSFKEELDKYFKNHTSPDVDLGD 1135
Cdd:cd22381   553 RGGLFVlpNNSNLWHFTKMNFYNPVNISYSNTQVLTSCSVNYTTVNYTVLNPSEPSDFNFQEEFDKWYKNQSSQFNNTFN 632
                         650       660       670       680       690       700       710       720
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1136 ISGINASVVNIQKEIDRLNEVAKNLNESLIDLQELGKYEQYIKWPWYVWLGFIAGLIAIVMVTILLCCMTSCCSCLKGAC 1215
Cdd:cd22381   633 PSDFNFSTVDVNEQLATLTDVVKQLNESFIDLKKLNVYEQTIKWPWYVWLAMIAGLVGLALAVVMLLCMTNCCSCFKGMC 712
                         730
                  ....*....|....*...
gi 442796478 1216 SCGSCCKFDEDDSEPVLK 1233
Cdd:cd22381   713 SCKQCQYDEVEDVYPAVR 730
SARS-CoV-like_Spike_S1_NTD cd21624
N-terminal domain of the S1 subunit of the Spike (S) protein from Severe acute respiratory ...
15-294 1.98e-174

N-terminal domain of the S1 subunit of the Spike (S) protein from Severe acute respiratory syndrome coronavirus and related betacoronaviruses in the B lineage; This subfamily contains the N-terminal domain (NTD) of the S1 subunit of the Spike (S) proteins from betacoronaviruses in the sarbecovirus subgenera (B lineage), including the highly pathogenic human coronavirus (CoV), Severe acute respiratory syndrome (SARS) CoV, and SARS-CoV-2, also known as a 2019 novel coronavirus (2019-nCoV) or COVID-19 virus. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). Most CoVs, including SARS-CoV-2 and SARS-CoV, use the C-domain to bind their receptors. The S1 NTD contributes to the Spike trimer interface.


Pssm-ID: 394950  Cd Length: 280  Bit Score: 515.73  E-value: 1.98e-174
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   15 EGCGVISNKPQRTFDQYSSTFRGVYYNDDIFRSDVLHLTQDYFLPFNTNVTRYLSLNAAQNTIVYFDNHVIPFYDGIYFA 94
Cdd:cd21624     1 EGCTTFSDKTAPNMTQYSSSRRGVYYPDDIFRSDVLVLTQDYFLPFNSNVTWYHSLNALGERKYYFDNPVLPFGDGVYFA 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   95 ATERSNVIRGWIFGSTFDNRSQSAIIVNNSTHILVKVCNFVLCTEPMFTVSR-NQHYKSWVYQHARNCTYDVAYPSFQLD 173
Cdd:cd21624    81 ATEKSNVVRGWIFGSTFDNTSQSAIIVNNGTHIIIRVCNFQLCKNPMFAVSKpGTQTNSWIYSNAFNCTYEYVSQSFQLD 160
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  174 VSLKnNVNFQHLREFIFKNVDGFLKIYSSYEPINVVSGIPSGFSVLKPVMSLPLGINITGMRVVMTMFSNTQANFLTENA 253
Cdd:cd21624   161 VSEK-NGNFKHLREFVFKNVDGFLKVYHGYQPINVVRGLPSGFSVLKPIFKLPLGINITNFRVVLTMFSPAQSNWTAGNA 239
                         250       260       270       280
                  ....*....|....*....|....*....|....*....|.
gi 442796478  254 AYYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKCTLK 294
Cdd:cd21624   240 AYYVGYLKPTTFMLKFDENGTITDAVDCSQDPLAELKCTLK 280
MERS-CoV-like_Spike_SD1-2_S1-S2_S2 cd22379
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
558-1178 1.47e-165

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from Middle East respiratory syndrome coronavirus and related betacoronaviruses in the C lineage; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses in the merbecovirus subgenus (C lineage), including Middle East respiratory syndrome coronavirus (MERS-CoV). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HCoV-KU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Rousettus bat coronavirus HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411966 [Multi-domain]  Cd Length: 682  Bit Score: 508.56  E-value: 1.47e-165
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  558 ISPCSFGGVSVITpgTNASTEVAVLYQDVNCTDVPTAINA-DQLTPAWRVYSTGINVFQTQAGCLIGAehVNASY---EC 633
Cdd:cd22379    44 VRPCVSVPVSVIY--DKSTNTHATLFGSVACEHISTMMSQfSRSTQSMLRRRSTNGPLQTAVGCVIGL--VNTSLtveDC 119
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  634 DIPIGAGICASYHTASVLRSTGQKSIVAYTMSLGAENSIAYANNS---IAIPTNFSISVTTEVMPVSMAKTSVDCTMYIC 710
Cdd:cd22379   120 KLPLGQSLCAVPPTLTPRSVSSVPGEQLASINFNHPLQVDQLNSSgfkVSIPTNFSFGVTQEYIQTTIQKVTVDCKQYVC 199
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  711 GDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVKQMYKTPAIKDFGG-FNFSqILPDPSKPT----KRSFI 785
Cdd:cd22379   200 NGFEKCEQLLREYGQFCSKINQALHGANLRQDDSVRNLFASIKTSQSQPLIAGLGGdFNLT-LLEPPSISTgsrsYRSAI 278
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  786 EDLLFNKVTLADAGFMKQYGECL--GDISARDLICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGWTFGAGAALQI 863
Cdd:cd22379   279 EDLLFDKVTIADPGYMQGYDECMkqGPPSARDLICAQYVAGYKVLPPLYDVNMEAAYTSSLLGSIAGAGWTAGLSSFAAI 358
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  864 PFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSV 943
Cdd:cd22379   359 PFAQSIFYRLNGVGITQQVLSENQKLIANKFNQALGAMQTGFTTTNLAFQKVQDAVNANAQALSKLASELSNTFGAISSS 438
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  944 LNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAA 1023
Cdd:cd22379   439 IGDILKRLDVLEQEAQIDRLINGRLTSLNAFVAQQLVRSETAARSAQLAKDKVNECVKSQSKRNGFCGQGTHIVSFVINA 518
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1024 PHGVVFLHVTYVPSQERNFTTAPAICHEG---KAYFPREGVFVSNGT-----SWFITQRNFYSPQIITTDNT-FVagSCN 1094
Cdd:cd22379   519 PNGLYFFHVGYVPTNHVNVTAAYGLCDSAnptNCIAPVNGYFIKNNTtrivdEWSYTGSSFYAPEPITSANTrYV--SPD 596
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1095 VVIGIINNTVYDPL---QPELDsFKEELDKYFKNHTSPDVDLGDISGINASVVNIQKEIDRLNEVAKNLNESLIDLQELG 1171
Cdd:cd22379   597 VTFQNLSNNLPPPLlsnSTDID-FKDELEEFFKNVSSQIPNFGSISQINTTLLDLSDEMLSLQQVVKALNESYIDLKELG 675

                  ....*..
gi 442796478 1172 KYEQYIK 1178
Cdd:cd22379   676 NYTYYQK 682
SARS-CoV-like_Spike_S1_RBD cd21477
receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related ...
309-512 7.39e-146

receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related coronavirus Spike (S) protein and similar proteins; This subfamily contains the receptor-binding domain of the S1 subunit of coronavirus (CoV) spike (S) proteins from highly pathogenic human virus, severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), SARS coronavirus 2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV), and other SARS-like coronaviruses. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2 and SARS-CoV use the C-domain to bind their receptors. Recent studies found that the receptor-binding domain (RBD) of SARS-CoV-2 S protein binds strongly to human and bat angiotensin-converting enzyme 2 (ACE2) receptors. Moreover, SARS-CoV-2 RBD exhibited significantly higher binding affinity to the ACE2 receptor than SARS-CoV RBD. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for SARS-CoV, SARS-CoV-2, and most CoVs.


Pssm-ID: 394824  Cd Length: 205  Bit Score: 438.10  E-value: 7.39e-146
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  309 RVSPTQEVVRFPNITNRCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 388
Cdd:cd21477     1 RVSPTTEVVRFPNITNLCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  389 TFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWNTANQDQGQYYYRSSRKEKLKPFERDLSSDEN-GVYTLSTYD 467
Cdd:cd21477    81 TFLIRGSEVRQVAPGQTGVIADYNYKLPDDFTGCVIAWNTAKQDNGNYYYRSHRKSKLKPFERDLSSDENsGVRTLSTYD 160
                         170       180       190       200
                  ....*....|....*....|....*....|....*....|....*
gi 442796478  468 FYPSVPLDYQATRVVVLSFELLNAPATVCGPKLSTTLVKNQCVNF 512
Cdd:cd21477   161 FNPTVPVGYQATRVVVLSFELLNAPATVCGPKLSTELVKNQCVNF 205
HKU1-CoV-like_Spike_SD1-2_S1-S2_S2 cd22380
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
516-1170 1.98e-145

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from human HKU1 and OC43 coronaviruses and related betacoronaviruses in the A lineage; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from betacoronaviruses in the embecovirus subgenus (A lineage), including highly pathogenic human coronaviruses (CoVs), HKU1 and OC43 CoVs, as well as murine hepatitis virus (MHV). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of MHV is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HCoV-KU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Rousettus bat coronavirus HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411967 [Multi-domain]  Cd Length: 663  Bit Score: 455.00  E-value: 1.98e-145
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  516 GLKGTGVLT-ASSKKFQSFQQFGRDASDFTDSVRDPQTLEILDISPCSFGGVSVITpGTNAStEVAVLYQDVNCTDVPTA 594
Cdd:cd22380     3 GITGQGIFKeVNADYYNSWQNLLYDSNGNLYGFRDYLTNKTYMIRSCYSGRVSAAF-HANAS-EPALLYRNLKCSYVFNN 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  595 INADQLTPawrvystgINVFQTQAGCLIGAEHVNASY--ECDIPIGAGICASYHTASVLR---STGQK--SIVAYTMSLg 667
Cdd:cd22380    81 TISREEQP--------LNYFDSYLGCVVNADNSTSSAvqTCDLRMGSGYCVDYSTSRRSRrsiSTGYRftTFEPFTVNL- 151
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  668 AENSIAYANN--SIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNT 745
Cdd:cd22380   152 VNDSVEPVGGlyEIQIPTNFTIGNHEEFIQTSSPKVTIDCAAFVCGDYAACRQQLVEYGSFCDNINAILNEVNELLDTTQ 231
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  746 QEVFAQVKQ------MYKTPAIKDFGGFNFSQIL----PDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGECLGDISARD 815
Cdd:cd22380   232 LQVANSLMQgvtlssRLKDGINFNVDDINFSPVLgclgSDCNAASSRSAIEDLLFDKVKLSDVGFVEAYNNCTGGAEIRD 311
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  816 LICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGWTFGAGaalqIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFN 895
Cdd:cd22380   312 LLCVQSFNGIKVLPPVLSENQISGYTTAATAASLFPPWSAAAG----VPFSLNVQYRINGLGVTMDVLSQNQKLIANAFN 387
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  896 KAISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYV 975
Cdd:cd22380   388 NALGAIQEGFDATNSALAKIQSVVNANAEALNNLLQQLSNRFGAISASLQEILSRLDALEAQAQIDRLINGRLTALNAYV 467
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  976 TQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQernFTTA---PAICHEG 1052
Cdd:cd22380   468 SQQLSDSTLVKFSAAQAIEKVNECVKSQSPRINFCGNGNHILSLVQNAPYGLYFIHFSYVPTS---FVTAkvsPGLCIAG 544
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1053 -KAYFPREGVFVSNGTSWFITQRNFYSPQIITTDNTFVAGSCNVVIG-----IINNTVydplqPELDSFKEELDKYFKNH 1126
Cdd:cd22380   545 dRGIAPKSGYFVNVNNEWMFTGSGYYYPEPITDKNVVVMSSCAVNYTkapdvMLNTSI-----PNLPDFKEELDQWFKNQ 619
                         650       660       670       680
                  ....*....|....*....|....*....|....*....|....
gi 442796478 1127 TSPDVDLGDISGINASVVNIQKEIDRLNEVAKNLNESLIDLQEL 1170
Cdd:cd22380   620 TSVAPDLSLDEYINVTFLDLQDEMNRIQEAIKVLNESYINLKEI 663
alphaCoV-HKU2-like_Spike_SD1-2_S1-S2_S2 cd22371
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the CoV ...
558-1221 2.35e-145

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the CoV spike (S) glycoprotein from Rhinolophus bat coronavirus HKU2 and related alphacoronaviruses; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from Wencheng shrew coronavirus (WESV), Lucheng Rn rat coronavirus (LRNV), and two bat viruses (Rhinolophus bat coronavirus HKU2 and BtRf-AlphaCoV/YN2012). Members of this group form a distinct cluster that is separated from the other alphacoronaviruses. The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HCoV-KU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Ro-BatCoV HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411958 [Multi-domain]  Cd Length: 686  Bit Score: 455.40  E-value: 2.35e-145
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  558 ISPCSFGGVSVITpgtNASTEVAVLYQDVNCtdvptainaDQL-TPAWRVYSTGINVFQTQAGCLIGAEHVN-ASYECDI 635
Cdd:cd22371    42 VEPCNEFSYSVLK---NNSSSYGTLYSGADC---------NQIdTKTFRFKARSHTGTNTSLGCLFNASYTNdTYTTCLN 109
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  636 PIGAGICASYHTAS--VLRSTGQKSIVAYTMSLGAENSIAyannsiaIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDS 713
Cdd:cd22371   110 PLGNGFCADVNVTSpvVGNIGIQKHDTDYVRPILTEQFIE-------LPLDHQLVVKEQFLQTSMPKFDVDCERYICDVS 182
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  714 LECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVKQMYKTPAIkDFGGFNFSQILPdpsKPTKRSFIEDLLFNKV 793
Cdd:cd22371   183 KACRELLFKYGGFCSKITADIKGSSILLDSQILGLYKTIAVDFSSPDV-DFGDFNFSMFMS---EKNGRSFIEDLLFDKI 258
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  794 TLADAGFMKQYGECLGDiSARDLICAQKFNGLTVLPPLLTDEMIAAYTAAlVSGTATAGwTFGaGAALQIPFAMQMAYRF 873
Cdd:cd22371   259 VTTGPGFYQDYYDCKKM-NLQDLTCAQYYNGIMVIPPIMDDETIGMYGGI-VAASMTAG-LFG-GQAGMVTWNTAMAGRL 334
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  874 NGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDK 953
Cdd:cd22371   335 NALGVTQDALVEDVNKLANGFNNLTQSVSKLAKTTSQALSAIQAVVNQNAAQVEQLVQGLSENFGAISNNFEVIAERLEK 414
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  954 VEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVT 1033
Cdd:cd22371   415 LEADQQMDRLINGRMNVLQNFVTNYKLKISELKSTQRLVQSLINECVYAQSLRNGFCGDGLHVMSLMQNAPDGIMFFHYT 494
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1034 YVPSQERNFTTAPAICHEGKAYFP----REGVFVS-NGTSWFITQRNFYSPQIITTDNTfVAGSCNVVIGIINNTVYDPL 1108
Cdd:cd22371   495 LKPNNTIIVKTTPGLCLSNEVCIKpidaKFGVLVSaNDSYWHFTPRNIYNPENITNSNI-IAVSGGANYTTVNNTIDIIE 573
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1109 QPELDSFKEELDKYFKNHTSPDVDLGDISgINASVVNIQKEIDRLNEVAKNLNESLIDLQELGKYEQYIKWPWYVWLGFI 1188
Cdd:cd22371   574 PPQNPPIDEEFRELYKNVTLELEQLKNIT-FDMSKLNLTYEIDRLNEIAENVSKLHVTVSEFNKYVQYVKWPWYVWLAIF 652
                         650       660       670
                  ....*....|....*....|....*....|....*
gi 442796478 1189 AGLIAIVMVTILLCCMTSCCSCLkGAC--SCGSCC 1221
Cdd:cd22371   653 LVLILFSFLMLWCCCATGCCGCC-GCCgaACNSCC 686
gammaCoV_Spike_SD1-2_S1-S2_S2 cd22372
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
681-1170 9.17e-141

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from avian infectious bronchitis coronavirus (IBV) and related gammacoronaviruses; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from gammacoronaviruses, including avian infectious bronchitis virus, and Beluga whale coronavirus SW1 (whale-CoV SW1). The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HCoV-KU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Ro-BatCoV HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411959 [Multi-domain]  Cd Length: 661  Bit Score: 442.50  E-value: 9.17e-141
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  681 IPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVKQM-YKTP 759
Cdd:cd22372   164 IPNSFNLTVTDEYIQTRMDKVQINCLQYVCGNSLECRKLFQQYGPVCDNILSIVNSVNQKEDMELLSFYSSTKPGgFNTP 243
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  760 AIKDF--GGFNFSQILPDPSKPTKRSFIEDLLFNKVTLADAGFMKQYGEC----LGdiSARDLICAQKFNGLTVLPPLLT 833
Cdd:cd22372   244 VFNNVstGGFNISLLLPPPSSPQGRSFIEDLLFTKVETVGLPTDDAYKKCtagpLG--FLKDLVCAQEYNGLLVLPPIIT 321
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  834 DEMIAAYTAALVSGTATAGWTfgagAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKAISQIQESLTTTSTALG 913
Cdd:cd22372   322 AEMQTMYTGSLVASMAFGGIT----AAGAIPFATQIQARINHLGITQSLLLKNQEKIAASFNKAIGHMQEGFRSTSLALQ 397
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  914 KLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAA 993
Cdd:cd22372   398 QIQDVVNKQSAILTETMASLNKNFGAISSVIQDIYQQLDAIQADAQVDRLITGRLSSLSVLASAKQAEYYKVSQQRELAT 477
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  994 TKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGK-----AYFPR--EGVFVS-N 1065
Cdd:cd22372   478 QKINECVKSQSNRYGFCGNGRHVLTIPQNAPNGIVFIHFTYTPESFVNVTAIVGFCVNPAngsqyAIVPAngRGIFIQvN 557
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1066 GTsWFITQRNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPL-QPELDSFKEELDKYFkNHTSPdvDLGDISGINASVV 1144
Cdd:cd22372   558 GT-YYITARDMYMPRDITAGDIVTLTSCQANYVSVNKTVITTFvDNDDFDFDDELSKWW-NETKH--ELPDFDQFNYTIP 633
                         490       500
                  ....*....|....*....|....*...
gi 442796478 1145 --NIQKEIDRLNEVAKNLNESLIDLQEL 1170
Cdd:cd22372   634 ilNISNEIDRIQEVIQGLNDSLIDLETL 661
alphaCoV_Spike_SD1-2_S1-S2_S2 cd22369
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
503-1170 7.21e-119

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) protein from alphacoronaviruses; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from alphacoronaviruses including human coronaviruses (HCoVs), HCoV-NL63, and HCoV-229E, and porcine coronaviruses, transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PEDV), among others. The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP), and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HKU1 the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Rousettus bat coronavirus HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411956 [Multi-domain]  Cd Length: 666  Bit Score: 384.33  E-value: 7.21e-119
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  503 TLVKNQCVNFNFNGLKGTGVLTASSKKFQSFQQFGRDASDFTdSVRDPQTLEILDISPCSFggvsvitpgtnaSTEVAVl 582
Cdd:cd22369     4 VVHLNVCTDYTIYGITGRGIIRKSNSTYIAGLYYTSNSGQLL-GFKNSTTGEVFSVTPCQL------------SSQVAV- 69
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  583 YQDvNCTDVPTAINADQLTpawRVYSTGINVFQTqagcligaeHVNASYECDIPI----GAGICASYHTASVLRSTGQKS 658
Cdd:cd22369    70 VSD-NIVGVMSATNNVSLG---FNNTIETPSFYY---------HSNGAENCTEPVltygSIGVCADGSITEVTPRSVSPE 136
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  659 IVAytmslgaenSIAYANnsIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIA 738
Cdd:cd22369   137 PVS---------PIITGN--ISIPSNFTVSVQVEYLQMYLKPVSVDCSTYVCNGNPRCLQLLTQYASACRTIEEALQLSA 205
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  739 -IEQDKNTQEVFAQVKQMYKTPAIKDFGGFNFSQILPdpSKPTKRSFIEDLLFNKVTLADAGFMKQ-YGECLGD--ISAR 814
Cdd:cd22369   206 rLESVEVNSMITVSEEALRLANISTFFDDYNLSAVLP--AGVGGRSAIEDLLFDKVVTSGLGTVDEdYKACTKGlgIAAA 283
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  815 DLICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGwtFGAGAAlqIPFAMQMAYRFNGIGVTQNVLYENQKQIANQF 894
Cdd:cd22369   284 DVACAQYYNGIMVLPGVVDAEKMALYTASLTGGMVLGG--FTAAAA--IPFSLAVQSRLNYVALQTDVLQRNQQILANSF 359
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  895 NKAISQI--------------QESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQI 960
Cdd:cd22369   360 NSAMGNItvafsevndaiqqtSDAINTVAQALNKVQNVVNEQGQALSQLTKQLASNFQAISSSIEDIYNRLDGLAADAQV 439
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  961 DRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQER 1040
Cdd:cd22369   440 DRLITGRLAALNAFVTQTLTKYTEVRASRQLAQQKINECVKSQSSRYGFCGNGTHLFSIVNAAPDGIMFLHTVLLPTEYV 519
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1041 NFTTAPAICHEGKAYFPREGV---FVSNGTSWFITQRNFYSPQIITTDNtFVA-GSCNVV-IGIINNTVYDPLQPELDSF 1115
Cdd:cd22369   520 TVAAWAGLCVDGKAYVLRDDVvltLFKLNDKYYVTPRDMFEPRVPVSSD-FVQiSNCNVTyVNITSDELPEVIPDYIDVN 598
                         650       660       670       680       690       700       710
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 442796478 1116 K--EELDKYFKNHTSPDVDLgDIsgINASVVNIQKEID--------------RLNEVAKNLNESLIDLQEL 1170
Cdd:cd22369   599 KtlEEFLANLPNYTLPDLPL-DI--FNATYLNLTGEIAdlenksesllnttvELQELIDNINNTLVDLEWL 666
delta-PiCoV-like_Spike_SD1-2_S1-S2_S2 cd22374
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
502-1220 1.54e-117

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from Pigeon coronavirus UAE-HKU29, and related avian deltacoronaviruses; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from Pigeon coronavirus UAE-HKU29, and related avian deltacoronaviruses including Falcon coronavirus UAE-HKU27, Magpie-robin coronavirus HKU18, Sparrow coronavirus HKU17, and Night heron coronavirus HKU19. The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the (C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HCoV-KU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Ro-BatCoV HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411961 [Multi-domain]  Cd Length: 739  Bit Score: 383.08  E-value: 1.54e-117
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  502 TTLVKNQCVNFNFNGLKGTGVLTASSKKFQSFQQFGRDASDFTdSVRDPQTLEILDISPCSFggvsvitpgtnaSTEVAV 581
Cdd:cd22374    21 STVYLDVCTKYNIYGKTGTGIIRLTNQSYIAGLYYTSPSGDLL-AFKNVTTQTVYSVTPCRL------------SSQVAV 87
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  582 LYQDVNCTDVPTAinadQLTPAWRVYSTGINVFQtqagcligaEHVNASYECDIPI----GAGICASyhtasvlrstGQK 657
Cdd:cd22374    88 YNGSIIAAFTSTE----NFTIADFTYSRATPMFY---------YHSIGNDTCETPVitfgSIGVCPG----------GGL 144
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  658 SIVAYTMSlGAENSIAYANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGI 737
Cdd:cd22374   145 HFVDPTSN-EFTNVVPISTQNISIPKNFTVSIQTEYIQIEQQPVTVDCRQYVCNGNPRCLQLLMQYTSACSTIEQALSLN 223
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  738 AIEQDKNTQEVFAQVKQMYKTPAIKDFG----GFNFSQILPdpSKPTKRSFIEDLLFNKVTLADAGFMKQ-YGECLGDIS 812
Cdd:cd22374   224 ARLEAASIQTMLTYSPETLKLANITNFQsddvNYNLTNILP--KKYQGRSAIEDLLFDKVVTNGLGTVDQdYKACTNGVS 301
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  813 ARDLICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGWTfgagAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIAN 892
Cdd:cd22374   302 IADLVCAQYYNGIMVLPGVADPEKMAQYTASLTGGMVFGGLT----SAAAIPFSLAVQSRLNYVALQTDVLQQNQQILAD 377
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  893 QFNKA--------------ISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEV 958
Cdd:cd22374   378 SFNNAmgnitlafkevsegLSQVSGAITTVANALTKIQTVVNSQGQALATLTEQLANNFQAISASIADIYNRLNQLEADA 457
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  959 QIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQ 1038
Cdd:cd22374   458 QVDRLITGRLAALNAFVTQTLSKLAEVRQARQLALDKINECVKSQSSRYGFCGNGTHLFSIVNAAPYGFVFFHTVLLPTQ 537
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1039 ERNFTTAPAICHEGKA---YFPREGVFVSNGTsWFITQRNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPE---L 1112
Cdd:cd22374   538 YATVQAYSGICQNGRAlalKDPSLALFRGTDK-YLVTPRNMYQPRTAAQADFVYIESCTVTYLNLTDTTIDAVIPDyvdV 616
                         650       660       670       680       690       700       710       720
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1113 DSFKEELDKYFKNHTSPDVDLG-----------DISGINASVVNIQKEIDRLNEVAKNLNESLIDLQELGKYEQYIKWPW 1181
Cdd:cd22374   617 NKTVEDILNNLPNYTKPDLDIGrynntilnlttEINDLNGRAENLSQIVENLEEYIKKINATLVDLEWLNRVETYIKWPW 696
                         730       740       750       760
                  ....*....|....*....|....*....|....*....|...
gi 442796478 1182 YVWLGFIAGLIAIV--MVTILLCcmTSCCsclkGAC--SCGSC 1220
Cdd:cd22374   697 WVWLLIALAITAFVciLVTIFLC--TGCC----GGCfgCCGGC 733
TGEV-like_Spike_SD1-2_S1-S2_S2 cd22377
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
504-1220 1.50e-114

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from transmissible gastroenteritis virus and related alphacoronaviruses; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from porcine transmissible gastroenteritis virus (TGEV), canine coronavirus (CCoV), and feline coronavirus (FCoV). They display greater than 96% sequence identity and have been grouped in the same species, alphacoronavirus 1, within the Alphacoronavirus genus. The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HKU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Rousettus bat coronavirus HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411964 [Multi-domain]  Cd Length: 751  Bit Score: 375.25  E-value: 1.50e-114
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  504 LVKNQCVNFNFNGLKGTGVLTASSKKFQSFQQFGRDASDFTdSVRDPQTLEILDISPCSFGGVSVITPGtnastEVAVLY 583
Cdd:cd22377     5 LVKDECTDYNIYGFQGTGIIRNTTSRLVAGLYYTSISGDLL-AFKNSTTGEIFTVVPCDLTAQAAVIND-----EIVGAI 78
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  584 QDVNCTDVPTAINADQLTPAWRVYSTGINVFQTQAGCLIGAEHVNASYECDIPI---GAGICasyhtasvlrSTGQKSIV 660
Cdd:cd22377    79 TSVNQTDLFEFVNHTQSRRSRRSTLGLVHTYTMPQFYYITKWNNDTSTNCTSVItysSFAIC----------NTGEIKYV 148
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  661 AYTMSLGAENSIAY----ANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRAL-T 735
Cdd:cd22377   149 NVTHVEIVDDSIGVikpiSTGNITIPKNFTVAVQAEYIQIQVKPVVVDCAKYVCNGNRHCLKLLTQYTSACQTIENALnL 228
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  736 GIAIE----------QDKNTQevFAQVKQMYKT-PAIKDFGGFNF---SQILPdpSKPTKRSFIEDLLFNKVTLADAGFM 801
Cdd:cd22377   229 GARLEslmlndmitvSDRSLE--LATVEKFNSTvLGGEKLGGFYFdglKDLLP--PRIGKRSAIEDLLFNKVVTSGLGTV 304
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  802 KQ-YGECLGDISARDLICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTAtagwtFGA-GAALQIPFAMQMAYRFNGIGVT 879
Cdd:cd22377   305 DDdYKKCSAGTDVADLVCAQYYNGIMVLPGVVDDNKMAMYTASLIGGMA-----LGSiTSAVAVPFAMQVQARLNYVALQ 379
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  880 QNVLYENQKQIANQFNKAI--------------SQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLN 945
Cdd:cd22377   380 TDVLQENQKILANAFNNAIgnitlalgkvsnaiTTTSDGFNTMASALTKIQSVVNQQGEALSQLTSQLQKNFQAISSSIA 459
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  946 DILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPH 1025
Cdd:cd22377   460 EIYNRLEKVEADAQVDRLITGRLAALNAYVSQTLTQYAEVKASRQLAMEKVNECVKSQSDRYGFCGNGTHLFSLVNSAPD 539
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1026 GVVFLHVTYVPSQERNFTTAPAIC-HEGKAYFPRE---GVFVSNGTsWFITQRNFYSPQIITTDNTFVAGSCNVVigiIN 1101
Cdd:cd22377   540 GLLFFHTVLLPTEWEEVTAWSGICvNDTYAYVLKDfltSIFSYNGT-YMVTPRNMFQPRKPQMSDFVQITSCEVT---FL 615
                         650       660       670       680       690       700       710       720
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1102 NTVYDPLQPEL-------DSFKEELDKYFKNHTSPDVDLGdISGINASVVNIQKEIDRLNEVA--------------KNL 1160
Cdd:cd22377   616 NTTYTTFQEIVidyidinKTIADMLEQYNPNYTVPELDLQ-LEIFNQTKLNLTAEIDQLEQRAdnltniahelqqyiDNL 694
                         730       740       750       760       770       780
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 442796478 1161 NESLIDLQELGKYEQYIKWPWYVWLgfIAGLIAIVMVTILL--CCMTSCCSClkgaCSC-GSC 1220
Cdd:cd22377   695 NKTLVDLEWLNRIETYVKWPWYVWL--LIGLVVVFCIPLLLfcCLSTGCCGC----FGClGSC 751
delta-PDCoV-like_Spike_SD1-2_S1-S2_S2 cd22373
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
507-1177 1.89e-106

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from porcine coronavirus HKU15, avian coronaviruses, and related deltacoronaviruses; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from porcine coronavirus PDCoV, and several avian coronaviruses such as quail deltacoronavirus (QdCoV) UAE-HKU30, white-eye coronavirus HKU16, common moorhen coronavirus HKU21, thrush CoV HKU12, and munia CoV HKU13, all from the Buldecovirus subgenus of deltacoronaviruses. The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HCoV-KU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Ro-BatCoV HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411960 [Multi-domain]  Cd Length: 648  Bit Score: 350.29  E-value: 1.89e-106
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  507 NQCVNFNFNGLKGTGVLTASSKKFQSFQQFGRDASDFTdSVRDPQTLEILDISPCSfggvsvitpgtnASTEVAVlyqdV 586
Cdd:cd22373     1 DVCTDYTIYGVSGTGIIKPSDLQLHNGIAFTSPTGELY-AFKNITTGKTYQVLPCE------------TPSQLIV----I 63
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  587 NCTDVpTAINADQLTpawrvystgINVFQTQAGCLIGAEHVNA-SYECDIPIgagicASYHTASVLrSTGqkSIVAYTMS 665
Cdd:cd22373    64 NNTIV-GAITSSNST---------ENGFTTTIVTPTFYYSTNAtSFNCTKPV-----LSYGPISVC-SDG--AIVGTSTL 125
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  666 LGAENSI-AYANNSIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKN 744
Cdd:cd22373   126 QDTRPSIvSLYDGEVEIPSAFTLSVQTEYLQVQAEQVVVDCPQYVCNGNSRCLQLLAQYTSACSNIESALHSSAQLDSRE 205
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  745 TQEVFAQVKQMYKTPAIKDF-GGFNFSQILPDpsKPTKRSFIEDLLFNKVTLADAGFMKQ-YGECLGDISARDLICAQKF 822
Cdd:cd22373   206 ITNMFQTSTQSLELANITNFkGDYNFTSILTT--KIGGRSAIEDLLFNKVVTNGLGTVDQdYKSCSKDMAIADLVCSQYY 283
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  823 NGLTVLPPLLTDEMIAAYTAALVSGTATAGWTfgagAALQIPFAMQMAYRFNGIGVTQNVLYENQKQIANQFNKA----- 897
Cdd:cd22373   284 NGIMVLPGVVDAEKMAMYTGSLTGAMVFGGLT----AAAAIPFSTAVQARLNYVALQTNVLQENQKILAESFNQAvgnis 359
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  898 ---------ISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRL 968
Cdd:cd22373   360 lalssvndaIQQTSEALNTVANAINKIQTVVNQQGEALSHLTAQLSNNFQAISTSIQDIYNRLDEVEANQQVDRLITGRL 439
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  969 QSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAI 1048
Cdd:cd22373   440 AALNAYVTQLLNQMSQIRQSRLLAQQKINECVKSQSSRYGFCGNGTHLFSITQAAPNGIFFMHAVLVPTKFTRVNASAGI 519
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1049 CHEGKAYFPREG--VFVSNGTSWFITQRNFYSPQIITTDNTFVAGSCNVVigiINNTVYDPLQ---PELDSFKEELDKYF 1123
Cdd:cd22373   520 CVDNTKGYSLQPqlILYQFNNSWRVTPRNMYEPRLPRQADFIPLTDCSVT---FYNTTAADLPniiPDYVDVNQTVSDII 596
                         650       660       670       680       690
                  ....*....|....*....|....*....|....*....|....*....|....
gi 442796478 1124 KNHTSPDVDLGDISGINASVVNIQKEIDRLNEVAKNLNESLIDLQelgkyeQYI 1177
Cdd:cd22373   597 DNLPTPTPPQLDVDIYNNTILNLTQEINDLQERSKNLSQIADRLQ------QYI 644
PDEV-like_Spike_SD1-2_S1-2_S2 cd22376
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
626-1174 2.99e-99

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from Porcine epidemic diarrhea virus and related alphacoronavirus; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from alphacoronaviruses, including porcine epidemic diarrhea virus (PEDV), Scotophilus bat coronavirus, and swine enteric coronavirus, among others. The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HKU1 the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Rousettus bat coronavirus HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411963 [Multi-domain]  Cd Length: 673  Bit Score: 331.34  E-value: 2.99e-99
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  626 HVNASYECDIPI----GAGICASYHTASVLRSTGQKSIVAytMSLGaensiayannSIAIPTNFSISVTTEVMPVSMAKT 701
Cdd:cd22376    98 HSNDGSNCTEPVlvysNIGVCKSGSIGYVPSQSGQPKIAP--MVTG----------NISIPTNFTMSIRTEYLQLYNTPV 165
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  702 SVDCTMYICGDSLECSNLLLQYGSFCTQLNRALTGIAIEQDKNTQEVFAQVKQMYKTPAIKDF--GGFNFSQILPdpSKP 779
Cdd:cd22376   166 SVDCAMYVCNGNSRCKQLLTQYTSACKTIESALQLSARLESVEVNSMLTISEEALQLATISSFngGGYNFTNVLG--ASV 243
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  780 TKRSFIEDLLFNKVTLADAGFMKQ-YGECLGDISARDLICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGWTfgAG 858
Cdd:cd22376   244 QKRSFIEDLLFNKVVTNGLGTVDEdYKRCSNGLSVADLVCAQYYSGVMVLPGVVDAEKLHMYSASLIGGMVLGGIT--AA 321
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  859 AALqiPFAMQMAYRFNGIGVTQNVLYENQKQIANQFN--------------KAISQIQESLTTTSTALGKLQDVVNQNAQ 924
Cdd:cd22376   322 AAL--PFSYAVQARLNYVALQTDVLQRNQQLLAESFNsaignitsafesvkEAISQTSQGLNTVAHALTKVQDVVNSQGA 399
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  925 ALNTLVKQLSSNFGAISSVLNDILSRLDKVEAEVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQS 1004
Cdd:cd22376   400 ALNQLTVQLQHNFQAISSSIDDIYSRLDQLSADAQVDRLITGRLSALNAFVAQTLTKYTEVQASRKLAQQKVNECVKSQS 479
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1005 KRVDFCG-KGYHLMSFPQAAPHGVVFLHVTYVPSQERNFTTAPAICHEGKAYF-PREGVFVSNG-------TSWFITQRN 1075
Cdd:cd22376   480 QRYGFCGgDGEHIFSLVQAAPQGLLFLHTVLVPGDFVNVTAIAGLCVDDEIALtLREPGVLFTHevltytaTEYFVSPRK 559
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1076 FYSPQIITTDNTFVAGSCNVV-IGIINNTVYDPLQPELDSFK--EELDKYFKNHTSPDVDLgDIsgINASVVNIQKEI-- 1150
Cdd:cd22376   560 MFEPRKPTVSDFVQIESCVVTyVNLTSDQLPDVIPDYIDVNKtlDEILASLPNRTGPSLPL-DV--FNATYLNLTGEIad 636
                         570       580       590
                  ....*....|....*....|....*....|....*.
gi 442796478 1151 ------------DRLNEVAKNLNESLIDLQELGKYE 1174
Cdd:cd22376   637 leqrseslrnttEELRSLIYNINNTLVDLEWLNRVE 672
HCoV-NL63-229E-like_Spike_SD1-2_S1-S2_S2 cd22375
SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) ...
502-1178 8.28e-99

SD-1 and SD-2 subdomains, the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoproteins from HCoV-NL63, HCoV-229E, and related alphacoronavirus; This group contains the SD-1 and SD-2 subdomains of the S1 subunit C-terminal domain (C-domain), the S1/S2 cleavage region, and the S2 fusion subunit of the spike (S) glycoprotein from alphacoronaviruses, including human coronaviruses (HCoVs), HCoV-NL63 and HCoV-229E. The CoV S protein is an envelope glycoprotein that plays a very important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains the coronavirus fusion machinery and is primarily alpha-helical. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-domain. The S1 C-domain also contains two subdomains (SD-1 and SD-2), which connect the S1 and S2 subunits. Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. The S2 subunit comprises the fusion peptide (FP), a second proteolytic site (S2'), followed by an internal fusion peptide (IFP) and two heptad-repeat domains (HR1 and HR2) preceding the transmembrane domain (TM). After binding of the S1 subunit RBD on the virion to its receptor on the target cell, the HR1 and HR2 domains interact with each other to form a six-helix bundle (6-HB) fusion core, bringing viral and cellular membranes into close proximity for fusion and infection. In order to catalyze the membrane fusion reaction, CoV S needs to be primed through cleavage at the S1/S2 and S2' sites. In the case of human-infecting coronaviruses such as SARS-CoV-2, HCoV-OC43, MERS-CoV, and HKU1, the spike protein contains an insertion of (R/K)-(2X)n-(R/K) (furin cleavage motif) at the S1/S2 site, which is absent in SARS-CoV and other SARS-related coronaviruses, as well as Rousettus bat coronavirus HKU9. The region modeled in this cd (SD-1 and SD-2, the S1/S2 cleavage region, and the S2 fusion subunit) plays an essential role in viral entry by initiating fusion of the viral and cellular membranes.


Pssm-ID: 411962 [Multi-domain]  Cd Length: 677  Bit Score: 329.94  E-value: 8.28e-99
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  502 TTLVKNQCVNFNFNGLKGTGVLTASSKKFQSFQQFGRDASDFTdSVRDPQTLEILDISPCsfggvsvitpgtNASTEVAV 581
Cdd:cd22375     3 SNVVLNNCTKYNIYDYSGTGVIRSSNDSFIGGITYTSNSGNLL-GFKDVSTGTIYSITPC------------NPPDQVVV 69
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  582 LYQDVnctdvPTAINADQLTpawrvySTGI-NVFQTQAGCLIGaehvNASYECDIPI----GAGICASYHTASVL-RSTG 655
Cdd:cd22375    70 YQQAI-----VGAMLSENET------RYGLsNVVELPNFYYAS----NGTYNCTDAVltysNFGICADGSIIPVRpRNVS 134
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  656 QKSIVAytmslgaensIAYANnsIAIPTNFSISVTTEVMPVSMAKTSVDCTMYICGDSLECSNLLLQYGSFCTQLNRALT 735
Cdd:cd22375   135 DNGVSA----------IVTAN--LSIPSNWTTSVQVEYLQITSTPIVVDCSTYVCNGNPRCVELLKQYTSACKTIEDALR 202
                         250       260       270       280       290       300       310       320
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  736 GIAIEQDKNTQEVFAQVKQMYKTPAIKDFGGFNFSQILP----DPSKPTKRSFIEDLLFNKVTLADAGFMK-QYGECLGD 810
Cdd:cd22375   203 LSARLESADVSSMLTFDSNAFTLANVSSFGDYNLSSVLPqlptSGSRIAGRSAIEDLLFSKVVTSGLGTVDaDYKSCTKG 282
                         330       340       350       360       370       380       390       400
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  811 ISARDLICAQKFNGLTVLPPLLTDEMIAAYTAALVSGTATAGWTfgagAALQIPFAMQMAYRFNGIGVTQNVLYENQKQI 890
Cdd:cd22375   283 LSIADLACAQYYNGIMVLPGVADAERMAMYTGSLIGGMALGGLT----SAAAIPFSLALQARLNYVALQTDVLQENQKIL 358
                         410       420       430       440       450       460       470       480
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  891 ANQFNKA--------------ISQIQESLTTTSTALGKLQDVVNQNAQALNTLVKQLSSNFGAISSVLNDILSRLDKVEA 956
Cdd:cd22375   359 AASFNKAmtnivdaftgvndaITQTSQAIQTVATALNKIQDVVNQQGNALNHLTSQLRQNFQAISSSIQAIYDRLDTIQA 438
                         490       500       510       520       530       540       550       560
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  957 EVQIDRLITGRLQSLQTYVTQQLIRAAEIRASANLAATKMSECVLGQSKRVDFCGKGYHLMSFPQAAPHGVVFLHVTYVP 1036
Cdd:cd22375   439 DQQVDRLITGRLAALNAFVSQTLTKYTEVRASRQLAQQKVNECVKSQSNRYGFCGNGTHIFSIVNAAPEGLVFLHTVLLP 518
                         570       580       590       600       610       620       630       640
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478 1037 SQERNFTTAPAICHEGKAYFPREG---VFVSNGTSWFITQRNFYSPQIITTDNTFVAGSCNVVIGIINNTVYDPLQPE-L 1112
Cdd:cd22375   519 TQYKDVEAWSGLCVDGVNGYVLRQpnlALYKDGGVFRITSRVMFEPRIPTMADFVQIENCNVTFVNISRSELQTIVPEyV 598
                         650       660       670       680       690       700       710
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 442796478 1113 DSFK--EELDKYFKNHTSPDVDL-----------GDISGINASVVNIQKEIDRLNEVAKNLNESLIDLQELGKYEQYIK 1178
Cdd:cd22375   599 DVNKtlQELIEKLPNYTVPDLDLdqynqtilnltSEISTLENKSAELNYTVQKLQTLIDNINSTLVDLKWLNRVETYIK 677
SARS-CoV-2_Spike_S1_RBD cd21480
receptor-binding domain of the S1 subunit of severe acute respiratory syndrome coronavirus 2 ...
309-512 1.28e-96

receptor-binding domain of the S1 subunit of severe acute respiratory syndrome coronavirus 2 Spike (S) protein; This group contains the receptor-binding domain of the S1 subunit of the spike (S) protein from highly pathogenic human virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as 2019 novel coronavirus (2019-nCoV). The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While RBD of mouse hepatitis virus (MHV) is located at the NTD, most of other CoVs, including SARS-CoV-2 use the C-domain to bind their receptors. Recent studies found that the receptor-binding domain (RBD) of SARS-CoV-2 S protein binds strongly to human and bat angiotensin-converting enzyme 2 (ACE2) receptors. Moreover, SARS-CoV-2 RBD exhibited significantly higher binding affinity to the ACE2 receptor than SARS-CoV RBD. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for SARS-CoV-2 and most CoVs.


Pssm-ID: 394827  Cd Length: 223  Bit Score: 307.79  E-value: 1.28e-96
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  309 RVSPTQEVVRFPNITNRCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 388
Cdd:cd21480     1 RVQPTESIVRFPNITNLCPFGEVFNATRFASVYAWNRKRISNCVADYSVLYNSASFSTFKCYGVSPTKLNDLCFTNVYAD 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  389 TFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWNTANQDQG-----QYYYRSSRKEKLKPFERDLSSDE------ 457
Cdd:cd21480    81 SFVIRGDEVRQIAPGQTGKIADYNYKLPDDFTGCVIAWNSNNLDSKvggnyNYLYRLFRKSNLKPFERDISTEIyqagst 160
                         170       180       190       200       210       220
                  ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 442796478  458 --NGV------YTLSTYDFYPSVPLDYQATRVVVLSFELLNAPATVCGPKLSTTLVKNQCVNF 512
Cdd:cd21480   161 pcNGVegfncyFPLQSYGFQPTNGVGYQPYRVVVLSFELLHAPATVCGPKKSTNLVKNKCVNF 223
bCoV_S1_N pfam16451
Betacoronavirus-like spike glycoprotein S1, N-terminal; This entry represents the N-terminal ...
31-324 9.15e-95

Betacoronavirus-like spike glycoprotein S1, N-terminal; This entry represents the N-terminal domain of the betacoronavirus-like trimeric spike glycoprotein. The distal S1 subunit of the coronavirus spike protein is responsible for receptor binding. S1 contains two domains; an N-terminal galectin-like domain (NTD) and a receptor-binding domain (S1 RBD) also referred to as the S1 CTD or domain B. Either the S1 NTD or S1 RBD, or occasionally both, are involved in binding to host receptors. S1 NTD is located on the side of the spike trimer and mainly recognizes sugar receptors. For many betacoronaviruses (b-CoVs), for example mouse hepatitis virus (MHV), the RBD is located in the NTD. The structure of the MHV S1 NTD showed the same fold as human galectins (galactose-binding lectin), however it does not bind any sugar; instead, it binds to the carcinoembryonic antigen cell-adhesion molecule CEACAM1) through protein-protein interactions. All three CEACAM21a-binding sites in MHV spikes can be fully occupied by CEACAM1a. It has been shown that CEACAM1a binding to the MHV spike weakens the interactions between S1 and S2 and facilitates the proteolysis of the spike protein and dissociation of S1. The homologous bovine CoV (BCov) S1 NTD also possesses a galectin fold but binds to sialic acid-containing moieties on host cell membranes, as does the NTD of three other group A b-Covs, namely human CoV (HCoV) OC43, avian b-CoV, and infectious bronchitis virus (IBV). Despite the S1 NTD of human respiratory b-CoV HKU1 being highly homologous to the NTDs of MHV and bovine CoV, it does not bind to either sugar or human carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) and the RBD is found instead in the S1 RBD domain.


Pssm-ID: 465119  Cd Length: 296  Bit Score: 305.49  E-value: 9.15e-95
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478    31 YSSTFRGVYY-NDDIFrSDVLHLTQDYFLPFNTNVTRYLSLNAAQNTIVYFDNHVIPFYDGIYFAATERSNVIRG----- 104
Cdd:pfam16451    1 DVSKADGTYYlPDRVY-SNTTTLRQGLFPKQGDNVTNYVYSPAHHCGKRNFSTPFLPFGDGIFVHIGNASNATGGriise 79
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   105 ---WIFGSTFDNRSQSAIIVNNS--THILVKVCNFVLCTEPMFTVS----RNQHYKSWVYQ-HARNCTYDVAYpSFQLDV 174
Cdd:pfam16451   80 ppaFVFGSTFGNTSHTLIIAPDScqTNLTILVCNFTLCANPVTACRwgagNYNANNSLVYFkNAINCTFNRTY-NITFDT 158
                          170       180       190       200       210       220       230       240
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   175 SLknnvnfqhlREFIFKNVDGFLKIYSSYEPInvvsGIPSGFSVLKPVMSLPLGINITGMRVVMTMFSNTQaNFLTENAA 254
Cdd:pfam16451  159 SL---------IYFGFKQQDGGFHIYYSYWLP----DLDSGPPTLFPFATLPLGINITYFQVIPSSIRSTQ-NCRRANAA 224
                          250       260       270       280       290       300       310
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 442796478   255 YYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKCTLKNFNITKGIYQTSNFRVSPTQEVV-RFPNITN 324
Cdd:pfam16451  225 YYVAPLKPSTFLLDFDVNGYITNAVDCSFDPLSELKCSTGSFEPDTGVYSTSSYRAQPVGSVYvRQPNVTC 295
SARS-CoV_Spike_S1_RBD cd21481
receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related ...
309-512 5.10e-92

receptor-binding domain of the S1 subunit of severe acute respiratory syndrome-related coronavirus Spike (S) protein; This group contains the receptor-binding domain of the S1 subunit of the spike (S) protein from severe acute respiratory syndrome-related coronavirus (SARS-CoV) and similar coronaviruses. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV use the C-domain to bind their receptors. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for SARS-CoV and most CoVs.


Pssm-ID: 394828  Cd Length: 222  Bit Score: 295.06  E-value: 5.10e-92
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  309 RVSPTQEVVRFPNITNRCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYAD 388
Cdd:cd21481     1 RVVPSGDVVRFPNITNLCPFGEVFNATKFPSVYAWERKKISNCVADYSVLYNSTFFSTFKCYGVSATKLNDLCFSNVYAD 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  389 TFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWNTANQDQG-----QYYYRSSRKEKLKPFERDLSSDE------ 457
Cdd:cd21481    81 SFVVKGDDVRQIAPGQTGVIADYNYKLPDDFMGCVLAWNTRNIDATstgnyNYKYRYLRHGKLRPFERDISNVPfspdgk 160
                         170       180       190       200       210       220
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 442796478  458 -------NGVYTLSTYDFYPSVPLDYQATRVVVLSFELLNAPATVCGPKLSTTLVKNQCVNF 512
Cdd:cd21481   161 pctppalNCYWPLNDYGFYTTTGIGYQPYRVVVLSFELLNAPATVCGPKLSTDLIKNQCVNF 222
CoV_Spike_S1_RBD cd21470
receptor-binding domain of the S1 subunit of coronavirus spike (S) proteins; This family ...
310-497 3.13e-57

receptor-binding domain of the S1 subunit of coronavirus spike (S) proteins; This family contains the receptor-binding domain (RBD) of the S1 subunit of coronavirus (CoV) spike (S) proteins from three highly pathogenic human coronaviruses (CoVs), including Middle East respiratory syndrome coronavirus (MERS-CoV), Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), and SARS coronavirus 2 (SARS-CoV-2), also known as a 2019 novel coronavirus (2019-nCoV), as well as S proteins from related coronaviruses. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV use the C-domain to bind their receptors. MHV uses mouse carcinoembryonic antigen related cell adhesion molecule 1a (mCEACAM1a) as the receptor, and the receptors for SARS-CoV and MERS-CoV are human angiotensin-converting enzyme 2 (ACE2) and human dipeptidyl peptidase 4 (DPP4), respectively. Recent studies found that the RBD of SARS-CoV-2 S protein binds strongly to human and bat angiotensin-converting enzyme 2 (ACE2) receptors. Moreover, SARS-CoV-2 RBD exhibited significantly higher binding affinity to the ACE2 receptor than SARS-CoV RBD. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs.


Pssm-ID: 394823  Cd Length: 171  Bit Score: 195.39  E-value: 3.13e-57
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  310 VSPTQEVVRFPNITNRCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYADT 389
Cdd:cd21470     1 VKPSGSVVRRPNNTPLCDFSEWLNATSVPSVYNWERKVFSNCNFNLSKLLSLFSVDSFTCNGISPAKIAGLCFSSITVDK 80
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  390 FLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWNTANQDQ---GQYYYRSSRKeklkpferdlssdengVYTLSTY 466
Cdd:cd21470    81 FAIPLSRKSDLQPGSAGFIQDYNYKIDFDNTSCQLAYNLPANNAtitKNHDYVYIQK----------------FLGWSTD 144
                         170       180       190
                  ....*....|....*....|....*....|.
gi 442796478  467 DFYPSvpldYQATRVVVLSFELLNAPATVCG 497
Cdd:cd21470   145 GCTSG----DQCQIFFNISFQYGNASGTVCS 171
CoV_Spike_S1_NTD cd21527
N-terminal domain of the S1 subunit of coronavirus Spike (S) proteins; This family contains ...
32-291 6.92e-56

N-terminal domain of the S1 subunit of coronavirus Spike (S) proteins; This family contains the N-terminal domain (NTD) of the S1 subunit of coronavirus (CoV) Spike (S) proteins from all four (A-D) lineages of betacoronaviruses, including three highly pathogenic human CoVs (HCoV) such as Middle East respiratory syndrome (MERS)-related CoV, Severe acute respiratory syndrome (SARS) CoV, and SARS-CoV-2, also known as a 2019 novel coronavirus (2019-nCoV) or COVID-19 virus. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). Most CoVs, including SARS-CoV-2, SARS-CoV and MERS-CoV, use the C-domain to bind their receptors. However, some CoVs from the A lineage, such as mouse hepatitis virus (MHV) uses the NTD to bind its receptor, mouse carcinoembryonic antigen related cell adhesion molecule 1a (mCEACAM1a). Bovine CoV and HCoV-OC43, also from the A lineage, recognize a sugar moiety, 5-N-acetyl-9-O-acetylneuraminic acid (Neu5,9Ac2), on cell-surface glycoproteins or glycolipids; this binding is also through the S1 NTD. The S1 NTD has also been the target for neutralizing antibodies, including human antibody CDC2-A2, and murine antibodies G2 and 5F9, which target MERS-CoV NTD. In addition, the S1 NTD contributes to the Spike trimer interface.


Pssm-ID: 394949  Cd Length: 268  Bit Score: 195.39  E-value: 6.92e-56
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   32 SSTFRGVYYNDDIFRSDVLHLTQDYFLPFNTNVTRY-LSLNAAQNTIVYFDNHVIPFYDGIYFAATER--------SNVI 102
Cdd:cd21527     9 VSKGLGTYYPDDRVYSNTTLLLQGLFPYDGSNFTNYaLKGSHALGTLWFYPPFVSPFNNGIFVKVKNTknstsatiYSEY 88
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  103 RGWIFGSTFDNRSQSAIIVNNSTHILVK--VCNFVLCTEPMF-----TVSRNQHYKSWVYQHARNCTYDVAYpsfqldvs 175
Cdd:cd21527    89 PAIVFGSTFGNTSYTVVIQPDNGGTLLEasACQYEMCEYNATicvpkTDGSDGNYSWHIDSNAFNCTFEYNF-------- 160
                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  176 lkNNVNFQHLREFIFKNVDGFLKIYSSYEPinvvsgiPSGFSVLKPVMSLPLGINITGMRVVMTMFSNTQANFLTENAAY 255
Cdd:cd21527   161 --TYNVNADLLYFGFYQEDGTLYAYYSDYV-------DLYGGPLKFLFSLPLGDNLTNYYVIPLTCRSIQSSDRKFAAAY 231
                         250       260       270
                  ....*....|....*....|....*....|....*.
gi 442796478  256 YVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKC 291
Cdd:cd21527   232 YVTYLTPRTFLLNFDENGVITNAVDCSSNFLSELKC 267
bCoV_S1_RBD pfam09408
Betacoronavirus spike glycoprotein S1, receptor binding; This entry represents the receptor ...
338-497 2.40e-40

Betacoronavirus spike glycoprotein S1, receptor binding; This entry represents the receptor binding domain (S1 RBD) of the betacoronavirus spike glycoprotein. The spike glycoprotein is arranged in trimers on the surface of the viral membrane and is essential for viral entry. The spike protein is translated as a large polypeptide that is subsequently cleaved to the distal S1, responsible for receptor binding, and the membrane-anchored S2 responsible for membrane fusion. The coronavirus (SARS-CoV) S1 subunit is composed of two distinct domains: an N-terminal domain (S1 NTD) and a receptor-binding domain (S1 RBD) also referred to as the S1 CTD or domain B. Each of these domains have been implicated in binding to host receptors. However, most coronaviruses are not known to utilize both the S1 NTD and S1 RBD for viral entry. SARS-CoV makes use of its S1 RBD to bind to the human angiotensin-converting enzyme 2 (ACE2) as its host receptor.


Pssm-ID: 462789  Cd Length: 156  Bit Score: 146.49  E-value: 2.40e-40
                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   338 PSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYADTFLIRSSEVRQVAPGETGVIADYNYKLPD 417
Cdd:pfam09408    1 PSPANWERKTFSNCNFDFSVLLSLLQVSSFKCYGVSPSKLADMCYGSVTIDYFAIPETHKSNLQPGSPGAISKYNYKLPD 80
                           90       100       110       120       130       140       150       160
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478   418 DFTGCVIAWNTANQDQ----GQYYYRSSRKEKLKPFERDLSSDENgvytlsTYDFYPSVPLDYQAtrVVVLSFELLNAPA 493
Cdd:pfam09408   81 DFYGCVLAFNVNANTNyafaDNYPYRYIKPGQYQPCNSFVSTVPN------SPDGHYCTPSSFNG--VVVITLKPATGSN 152

                   ....
gi 442796478   494 TVCG 497
Cdd:pfam09408  153 LVCP 156
bat_HKU4-like_Spike_S1_RBD cd21487
receptor-binding domain of the S1 subunit of the Spike (S) protein from Tylonycteris bat ...
310-414 1.23e-09

receptor-binding domain of the S1 subunit of the Spike (S) protein from Tylonycteris bat coronavirus HKU4 and similar proteins; This group contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from Tylonycteris bat coronavirus HKU4 and other Middle East Respiratory Syndrome (MERS)-related coronaviruses. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including human MERS-CoV that is phylogenetically closely related to bat CoV HKU4 use the C-domain to bind their receptors. HKU4 is able to bind the MERS-CoV receptor, human dipeptidyl peptidase 4 (DPP4), also called CD26. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs including MERS-CoV, and most likely, bat CoV HKU4.


Pssm-ID: 394834  Cd Length: 219  Bit Score: 59.61  E-value: 1.23e-09
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  310 VSPTQEVVRFPNITnRCPFDKVFNATRfPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYADT 389
Cdd:cd21487     1 ASATGTFIEQPNAT-ECDFSPMLTGVA-PQVYNFKRLVFSNCNYNLTKLLSLFAVDEFSCNGISPDAIARGCYSTLTVDY 78
                          90       100
                  ....*....|....*....|....*
gi 442796478  390 FLIRSSEVRQVAPGETGVIADYNYK 414
Cdd:cd21487    79 FAYPLSMKSYIRPGSAGNIPLYNYK 103
HKU1-like_CoV_Spike_S1_RBD cd21478
receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus HKU1 ...
306-422 2.60e-09

receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus HKU1 and related coronaviruses; This family contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from human coronavirus (CoV) HKU1, human coronavirus OC43 (HCoV-OC43), mouse hepatitis virus (MHV), porcine hemagglutinating encephalomyelitis virus (HEV), and other related coronaviruses. HKU1 is a human betacoronavirus that causes mild yet prevalent respiratory disease. HCoV-OC43 is of zoonotic origin and is endemic in the human population, causing mild respiratory tract infections and possible severe complications or fatalities in young children, the elderly, and immunocompromised individuals. MHV is the most common viral pathogen in contemporary laboratory mouse colonies manifesting as a primary infection in the upper respiratory tract. Porcine HEV is associated with acute outbreaks of wasting and encephalitis in nursing piglets from pig farms. These viruses are related to the zoonotic SARS and MERS betacoronaviruses, which have high fatality rates and pandemic potential. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBDs of MHV and HCoV-OC43 are located at the NTD, most CoVs use the C-domain to bind their receptors. Although a protein receptor has not yet been identified for HKU1, antibodies against the C-domain, but not those against the NTD, blocked HKU1 infection of cells, suggesting that the S1 C-domain is the primary HKU1 receptor-binding site. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs.


Pssm-ID: 394825  Cd Length: 223  Bit Score: 59.01  E-value: 2.60e-09
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  306 SNFRVSPTQEVVR-FPNITNrCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTS 384
Cdd:cd21478     1 TGYTVQPIADVYRrIPNLPD-CDIEEWLNAPTVPSPLNWERKTFSNCNFNMSSLLSLVQADSFSCNNIDASKIYGMCFGS 79
                          90       100       110
                  ....*....|....*....|....*....|....*...
gi 442796478  385 VYADTFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGC 422
Cdd:cd21478    80 ITIDKFAIPNSRKVDLQLGSSGYLQSFNYRIDTAATSC 117
HCoV-OC43-like_Spike_S1_RBD cd21485
receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus OC43 ...
308-427 4.68e-09

receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus OC43 and related proteins; This group contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from several betacoronaviruses including human coronavirus OC43 (HCoV-OC43) and bovine respiratory coronavirus (BCoV), among others. HCoV-OC43 is of zoonotic origin and is endemic in the human population, causing mild respiratory tract infections and possible severe complications or fatalities in young children, the elderly, and immunocompromised individuals. These viruses are related to the zoonotic SARS and MERS betacoronaviruses, which have high fatality rates and pandemic potential. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs use the C-domain to bind their receptors. It has been reported that HCoV-OC43 uses 9-O-acetyl-sialic acid (9-O-Ac-Sia) as a receptor, which is terminally linked to oligosaccharides decorating glycoproteins and gangliosides at the host cell surface. HCoV-OC43 appears to bind 9-O-Ac-Sia at the NTD. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs.


Pssm-ID: 394832  Cd Length: 312  Bit Score: 59.25  E-value: 4.68e-09
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  308 FRVSPTQEVVR-FPNITNrCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVY 386
Cdd:cd21485     3 YTVQPIADVYRrIPNLPD-CNIEAWLNDKSVPSPLNWERKTFSNCNFNMSSLMSFIQADSFTCNNIDAAKIYGMCFSSIT 81
                          90       100       110       120
                  ....*....|....*....|....*....|....*....|.
gi 442796478  387 ADTFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWN 427
Cdd:cd21485    82 IDKFAIPNGRKVDLQLGNLGYLQSFNYRIDTTATSCQLYYN 122
HKU1_N1_CoV_Spike_S1_RBD cd21483
receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus HKU1, ...
306-427 1.92e-08

receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus HKU1, isolate N1; This group contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from human coronavirus (CoV) HKU1, isolate N1. HKU1 is a human betacoronavirus that causes mild yet prevalent respiratory disease, and is related to the zoonotic SARS and MERS betacoronaviruses, which have high fatality rates and pandemic potential. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs use the C-domain to bind their receptors. Although a protein receptor has not yet been identified for HKU1, antibodies against the C-domain, but not those against the NTD, blocked HKU1 infection of cells, suggesting that the S1 C-domain is the primary HKU1 receptor-binding site. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs, and most likely, for HKU1.


Pssm-ID: 394830  Cd Length: 306  Bit Score: 57.43  E-value: 1.92e-08
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  306 SNFRVSPTQEV-VRFPNITNrCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTS 384
Cdd:cd21483     1 SGFTVKPVATVhRRIPDLPD-CDIDKWLNNFNVPSPLNWERKIFSNCNFNLSTLLRLVHTDSFSCNNFDESKIYGSCFKS 79
                          90       100       110       120
                  ....*....|....*....|....*....|....*....|...
gi 442796478  385 VYADTFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWN 427
Cdd:cd21483    80 IVLDKFAIPNSRRSDLQLGSSGFLQSSNYKIDTTSSSCQLYYS 122
batCoV-HKU9-like_Spike_S1_NTD cd21627
N-terminal domain of the S1 subunit of the Spike (S) protein from Rousettus bat coronavirus ...
104-291 2.89e-08

N-terminal domain of the S1 subunit of the Spike (S) protein from Rousettus bat coronavirus HKU9 and related betacoronaviruses in the D lineage; This subfamily contains the N-terminal domain (NTD) of the S1 subunit of the Spike (S) proteins from betacoronaviruses in the nobecovirus subgenera (D lineage), including Rousettus bat coronavirus HKU9 and related bat CoVs. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). Most CoVs, including SARS-CoV-2, SARS-CoV, and MERS-CoV use the C-domain to bind their receptors. However, CoV such as mouse hepatitis virus (MHV) uses the NTD to bind its receptor, mouse carcinoembryonic antigen related cell adhesion molecule 1a (mCEACAM1a). The S1 NTD contributes to the Spike trimer interface.


Pssm-ID: 394953  Cd Length: 289  Bit Score: 56.59  E-value: 2.89e-08
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  104 GWIFGSTFDNR-------------SQSAIIVNNSTHILVKVC-NFVLCTEPMFT---VSRNQHYKSWVYQHARNCTYDva 166
Cdd:cd21627    91 GVAFGNTFEQDriaiviiapgnlgSWPAVSKRTTTNVHILVCsNATLCANPAFNrwgPAGSIYASDAFVCHGNSCFVN-- 168
                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  167 yPSFQLDVSlKNNVNFQhlreFIFKnvDGFLKIYssYEPINVVSG--IPSGFSvLKPVMSLPLGINITGMR----VVMTM 240
Cdd:cd21627   169 -NTFIIPIN-TSRINLA----FRFK--DGNLLLY--HSAWLPTSGlnLSGDYP-LHYYMSVPVGFNLPNAQffqsVVRPN 237
                         170       180       190       200       210
                  ....*....|....*....|....*....|....*....|....*....|.
gi 442796478  241 FSNTQANFLTENAAYYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKC 291
Cdd:cd21627   238 TEPADGACAAFQNNLYIAPLSKRELLVSYDDNGSPVNVADCSADAGSELYC 288
HKU1_N5-like_CoV_Spike_S1_RBD cd21482
receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus HKU1, ...
306-427 4.31e-08

receptor-binding domain of the S1 subunit of the Spike (S) protein from human coronavirus HKU1, isolate N5 and isolate N2; This group contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from human coronavirus (CoV) HKU1, isolates N5 and N2. HKU1 is a human betacoronavirus that causes mild yet prevalent respiratory disease, and is related to the zoonotic SARS and MERS betacoronaviruses, which have high fatality rates and pandemic potential. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs use the C-domain to bind their receptors. Although a protein receptor has not yet been identified for HKU1, antibodies against the C-domain, but not those against the NTD, blocked HKU1 infection of cells, suggesting that the S1 C-domain is the primary HKU1 receptor-binding site. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs, and most likely, for HKU1.


Pssm-ID: 394829  Cd Length: 304  Bit Score: 56.23  E-value: 4.31e-08
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  306 SNFRVSPTQEVVR-FPNITNrCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTS 384
Cdd:cd21482     1 SGFTVKPVATVYRrIPNLPD-CDIDNWLNNVSVPSPLNWERRIFSNCNFNLSTLLRLVHVDSFSCNNLDKSKIFGSCFNS 79
                          90       100       110       120
                  ....*....|....*....|....*....|....*....|...
gi 442796478  385 VYADTFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWN 427
Cdd:cd21482    80 ITVDKFAIPNRRRDDLQLGSSGFLQSSNYKIDISSSSCQLYYS 122
HEV_Spike_S1_RBD cd21508
receptor-binding domain of the S1 subunit of the Spike (S) protein from porcine ...
306-441 6.68e-08

receptor-binding domain of the S1 subunit of the Spike (S) protein from porcine hemagglutinating encephalomyelitis virus; This group contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from porcine hemagglutinating encephalomyelitis virus (HEV), which is associated with acute outbreaks of wasting and encephalitis in nursing piglets from pig farms. Porcine HEV is related to the zoonotic SARS and MERS betacoronaviruses, which have high fatality rates and pandemic potential. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs use the C-domain to bind their receptors. The protein receptor for porcine HEV has not yet been identified. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs.


Pssm-ID: 394835  Cd Length: 298  Bit Score: 55.52  E-value: 6.68e-08
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  306 SNFRVSPTQEVVR-FPNITNrCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTS 384
Cdd:cd21508     1 NGYTVQPVATVYRrIPDLPN-CDIEAWLNSKTVSSPLNWERKIFSNCNFNMGRLMSFIQADSFGCNNIDASRLYGMCFGS 79
                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 442796478  385 VYADTFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGCVIAWNTANQDQGQYYYRSS 441
Cdd:cd21508    80 ITIDKFAIPNSRKVDLQVGKSGYLQSFNYKIDTAVSSCQLYYSLPAANVSVTHYNPS 136
MHV-like_Spike_S1_RBD cd21484
receptor-binding domain of the S1 subunit of the Spike (S) protein from mouse hepatitis virus ...
306-422 1.97e-07

receptor-binding domain of the S1 subunit of the Spike (S) protein from mouse hepatitis virus and other rodent coronaviruses; This group contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from mouse hepatitis virus (MHV) and other rodent coronaviruses. MHV is the most common viral pathogen in contemporary laboratory mouse colonies manifesting as a primary infection in the upper respiratory tract. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). MHV uses mouse carcinoembryonic antigen related cell adhesion molecule 1a (mCEACAM1a) as the receptor; the RBD of MHV is located at the NTD. Most CoVs, such as SARS-CoV and MERS-CoV, use the C-domain to bind their receptors. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs.


Pssm-ID: 394831  Cd Length: 264  Bit Score: 53.73  E-value: 1.97e-07
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  306 SNFRVSPTQEVVR-FPNITNrCPFDKVFNATRFPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTS 384
Cdd:cd21484     1 SGYTVQPVGVVYRrVPNLPD-CKIEEWLTAKSVPSPLNWERKTFQNCNFNLSSLLRYVQAESLSCNNIDASKVYGMCFGS 79
                          90       100       110
                  ....*....|....*....|....*....|....*...
gi 442796478  385 VYADTFLIRSSEVRQVAPGETGVIADYNYKLPDDFTGC 422
Cdd:cd21484    80 ISIDKFAIPNSRRVDLQLGNSGFLQSFNYKIDTRATSC 117
MERS-like_CoV_Spike_S1_RBD cd21479
receptor-binding domain of the S1 subunit of the Spike (S) protein from Middle East ...
310-414 2.41e-07

receptor-binding domain of the S1 subunit of the Spike (S) protein from Middle East respiratory syndrome coronavirus; This family contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from the human coronavirus that causes Middle East Respiratory Syndrome (MERS-CoV) and related coronaviruses from animals. MERS-CoV causes severe pulmonary disease in humans. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including MERS-CoV use the C-domain to bind their receptors. MERS-CoV use human dipeptidyl peptidase 4 (DPP4), also called CD26, as its receptor. It binds DPP4 through the RBD of its S1 subunit and then fuses viral and host membranes through its S2 subunit. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs including MERS-CoV.


Pssm-ID: 394826  Cd Length: 216  Bit Score: 52.78  E-value: 2.41e-07
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  310 VSPTQEVVRFPNITNrCPFDKVFNATRfPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYADT 389
Cdd:cd21479     1 AKPRGTFIEQAEGVE-CDFSPLLKGTP-PQVYNFKRLVFTNCNYNLTKLLSLFQVDEFSCHQISPSALATGCYSSLTVDY 78
                          90       100
                  ....*....|....*....|....*
gi 442796478  390 FLIRSSEVRQVAPGETGVIADYNYK 414
Cdd:cd21479    79 FAYPLSMKSYLQPGSAGPIVQFNYK 103
MHV-like_Spike_S1_NTD cd21625
N-terminal domain of the S1 subunit of the Spike (S) protein from murine hepatitis virus and ...
247-291 1.70e-05

N-terminal domain of the S1 subunit of the Spike (S) protein from murine hepatitis virus and related betacoronaviruses in the A lineage; This subfamily contains the N-terminal domain (NTD) of the S1 subunit of the Spike (S) proteins from betacoronaviruses in the embecovirus subgenera (A lineage), including murine hepatitis virus (MHV), human coronavirus (HCoV) HKU1 and OC43, and bovine CoV (BCoV). MHV is the most common viral pathogen in contemporary laboratory mouse colonies manifesting as a primary infection in the upper respiratory tract, while HCoV-HKU1 causes mild yet prevalent respiratory disease in humans. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While most CoVs, including SARS-CoV and MERS-CoV use the C-domain to bind their receptors, several CoVs in the A lineage use the NTD to bind their receptors. MHV binds its protein receptor, mouse carcinoembryonic antigen related cell adhesion molecule 1a (mCEACAM1a), through its S1 NTD. BCoV and HCoV-OC43 recognize a sugar moiety, 5-N-acetyl-9-O-acetylneuraminic acid (Neu5,9Ac2), on cell-surface glycoproteins or glycolipids; this binding is also through the S1 NTD. In addition, the S1 NTD contributes to the Spike trimer interface.


Pssm-ID: 394951  Cd Length: 284  Bit Score: 48.16  E-value: 1.70e-05
                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 442796478  247 NFLTENAAYYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKC 291
Cdd:cd21625   238 NSTALTLEYWVTPLTKRQYLLAFNQDGVITNAVDCASDFMSEIKC 282
MERS-CoV-like_Spike_S1_NTD cd21626
N-terminal domain of the S1 subunit of the Spike (S) protein from Middle East respiratory ...
253-292 1.79e-05

N-terminal domain of the S1 subunit of the Spike (S) protein from Middle East respiratory syndrome-related coronavirus and related betacoronaviruses in the C lineage; This subfamily contains the N-terminal domain (NTD) of the S1 subunit of the Spike (S) proteins from betacoronaviruses in the merbecovirus subgenera (C lineage), including the highly pathogenic human coronavirus (CoV), Middle East respiratory syndrome (MERS)-related CoV, and related bat CoVs. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). Most CoVs, including MERS-CoV, use the C-domain to bind their receptors. Despite using the C-domain as its receptor, neutralizing antibodies targeting MERS-CoV S1-NTD have been reported, including human antibody CDC2-A2, murine antibodies G2 and 5F9, and macaque antibodies FIB-H1 and JC57-13. G2 has been shown to strongly disrupt the attachment of MERS-CoV S to its receptor, dipeptidyl peptidase-4 (DPP4). In addition, the S1 NTD contributes to the Spike trimer interface.


Pssm-ID: 394952  Cd Length: 328  Bit Score: 48.50  E-value: 1.79e-05
                          10        20        30        40
                  ....*....|....*....|....*....|....*....|
gi 442796478  253 AAYYVGYLKPRTFMLQFNTNGTIVNAVDCSQDPLSELKCT 292
Cdd:cd21626   289 AAFYIYKLHPLTYLLDFDVDGYIRRAIDCGYDDLSQLQCS 328
CoV_S2_C pfam19214
Coronavirus spike glycoprotein S2, intravirion; This entry represents the cysteine rich ...
1200-1239 2.19e-05

Coronavirus spike glycoprotein S2, intravirion; This entry represents the cysteine rich intravirion region found at the C-terminus of coronavirus spike proteins (S). These cysteine residues are targets for palmitoylation, necessary for efficiently S incorporation into virions and S-mediated membrane fusions.


Pssm-ID: 465998  Cd Length: 42  Bit Score: 42.79  E-value: 2.19e-05
                           10        20        30        40
                   ....*....|....*....|....*....|....*....|..
gi 442796478  1200 LLCCMTSCCSCLKGaCSCGSCC-KFDE-DDSEPVLKGVKLHY 1239
Cdd:pfam19214    1 FCCCCTGCCGCCFG-CSCGGCCdSYDKrDDVYPAEVVEKVHV 41
human_MERS-CoV_Spike_S1_RBD cd21486
receptor-binding domain of the S1 subunit of the Spike (S) protein from human Middle East ...
326-424 8.33e-05

receptor-binding domain of the S1 subunit of the Spike (S) protein from human Middle East respiratory syndrome coronavirus; This group contains the receptor-binding domain (RBD) of the S1 subunit of the spike (S) protein from the human coronavirus that causes Middle East Respiratory Syndrome (MERS-CoV). MERS-CoV causes severe pulmonary disease in humans. The CoV S protein is an envelope glycoprotein that plays the most important role in viral attachment, fusion, and entry into host cells, and serves as a major target for the development of neutralizing antibodies, inhibitors of viral entry, and vaccines. It is synthesized as a precursor protein that is cleaved into an N-terminal S1 subunit (~700 amino acids) and a C-terminal S2 subunit (~600 amino acids) that mediates attachment and membrane fusion, respectively. Three S1/S2 heterodimers assemble to form a trimer spike protruding from the viral envelope. The S1 subunit contains a receptor-binding domain (RBD), while the S2 subunit contains a hydrophobic fusion peptide and two heptad repeat regions. S1 contains two structurally independent domains, the N-terminal domain (NTD) and the C-terminal domain (C-domain). Depending on the virus, either the NTD or the C-domain can serve as the receptor-binding domain (RBD). While the RBD of mouse hepatitis virus (MHV) is located at the NTD, most CoVs, including MERS-CoV use the C-domain to bind their receptors. MERS-CoV use human dipeptidyl peptidase 4 (DPP4), also called CD26, as its receptor. It binds DPP4 through the RBD of its S1 subunit and then fuses viral and host membranes through its S2 subunit. Due to the key role of the S protein RBD in viral attachment, it is the major target for antibody-mediated neutralization. This model corresponds to the S1 subunit C-domain that serves as the RBD for most CoVs including MERS-CoV.


Pssm-ID: 394833  Cd Length: 219  Bit Score: 45.51  E-value: 8.33e-05
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 442796478  326 CPFDKVFNATRfPSVYAWERTKISDCVADYTVLYNSTSFSTFKCYGVSPSKLIDLCFTSVYADTFLIRSSEVRQVAPGET 405
Cdd:cd21486    16 CDFSPLLSGTP-PQVYNFKRLVFTNCNYNLTKLLSLFSVNDFTCSQISPAAIASNCYSSLILDYFSYPLSMKSDLSVSSA 94
                          90
                  ....*....|....*....
gi 442796478  406 GVIADYNYKLPDDFTGCVI 424
Cdd:cd21486    95 GPISQFNYKQSFSNPTCLI 113
 
Blast search parameters
Data Source: Precalculated data, version = cdd.v.3.21
Preset Options:Database: CDSEARCH/cdd   Low complexity filter: no  Composition Based Adjustment: yes   E-value threshold: 0.01

References:

  • Wang J et al. (2023), "The conserved domain database in 2023", Nucleic Acids Res.51(D)384-8.
  • Lu S et al. (2020), "The conserved domain database in 2020", Nucleic Acids Res.48(D)265-8.
  • Marchler-Bauer A et al. (2017), "CDD/SPARCLE: functional classification of proteins via subfamily domain architectures.", Nucleic Acids Res.45(D)200-3.
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