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Conserved domains on  [gi|1186517920|ref|NP_001337890|]
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mitochondrial inner membrane protease subunit 2 isoform b [Homo sapiens]

Protein Classification

S26 family signal peptidase( domain architecture ID 1011306)

S26 family signal peptidase is a membrane-bound serine protease which frees proteins tethered to inner or mitochondrial membranes by cleaving off signal peptides during polypeptide translocation

EC:  3.4.21.-
Gene Ontology:  GO:0004252|GO:0006465
MEROPS:  S26
PubMed:  10982814

Graphical summary

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List of domain hits

 Name Accession Description Interval E-value
Peptidase_S26 super family cl37809
Signal peptidase, peptidase S26; This is a family of membrane signal serine endopeptidases ...
 9-179 1.21e-18

Signal peptidase, peptidase S26; This is a family of membrane signal serine endopeptidases which function in the processing of newly-synthesized secreted proteins. Peptidase S26 removes the hydrophobic, N-terminal, signal peptides as proteins are translocated across membranes. The active site residues take the form of a catalytic dyad that is Ser, Lys in subfamily S26A; the Ser is the nucleophile in catalysis, and the Lys is the general base.


The actual alignment was detected with superfamily member pfam10502:

Pssm-ID: 431321 [Multi-domain]  Cd Length: 162  Bit Score: 78.79  E-value: 1.21e-18
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920   9 KRYIKAFckgfFVAVPVAVTFldRVACVA--RVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIVslvlltvtp 86
Cdd:pfam10502   2 LEWVKAI----VIALLLALLI--RTFLFEpyVVPGGSMSPTLPIG-----DYLIVNKFSYGLGEPKRGDIV--------- 61

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  87 strqqeiggeeeevekdisLAKSPKNPEQKIIKRVIALEGDIVR---------------------------TIGHKNRYV 139
Cdd:pfam10502  62 -------------------VFRPPEGPGVPLIKRVIGLPGDRVEykddqlyingkpvgepyladrkgrptfDLPPWQGCR 122

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1186517920 140 KVPRGHIWVEGDHHGHSFDSNSFGPVSLGLLHAHATHILW 179
Cdd:pfam10502 123 VVPEGEYFVMGDNRDNSLDSRYFGFVPASNIVGRAVFPVW 162
 
Name Accession Description Interval E-value
Peptidase_S26 pfam10502
Signal peptidase, peptidase S26; This is a family of membrane signal serine endopeptidases ...
 9-179 1.21e-18

Signal peptidase, peptidase S26; This is a family of membrane signal serine endopeptidases which function in the processing of newly-synthesized secreted proteins. Peptidase S26 removes the hydrophobic, N-terminal, signal peptides as proteins are translocated across membranes. The active site residues take the form of a catalytic dyad that is Ser, Lys in subfamily S26A; the Ser is the nucleophile in catalysis, and the Lys is the general base.


Pssm-ID: 431321 [Multi-domain]  Cd Length: 162  Bit Score: 78.79  E-value: 1.21e-18
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920   9 KRYIKAFckgfFVAVPVAVTFldRVACVA--RVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIVslvlltvtp 86
Cdd:pfam10502   2 LEWVKAI----VIALLLALLI--RTFLFEpyVVPGGSMSPTLPIG-----DYLIVNKFSYGLGEPKRGDIV--------- 61

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  87 strqqeiggeeeevekdisLAKSPKNPEQKIIKRVIALEGDIVR---------------------------TIGHKNRYV 139
Cdd:pfam10502  62 -------------------VFRPPEGPGVPLIKRVIGLPGDRVEykddqlyingkpvgepyladrkgrptfDLPPWQGCR 122

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1186517920 140 KVPRGHIWVEGDHHGHSFDSNSFGPVSLGLLHAHATHILW 179
Cdd:pfam10502 123 VVPEGEYFVMGDNRDNSLDSRYFGFVPASNIVGRAVFPVW 162
sigpep_I_bact TIGR02227
signal peptidase I, bacterial type; This model represents signal peptidase I from most ...
 33-180 1.94e-18

signal peptidase I, bacterial type; This model represents signal peptidase I from most bacteria. Eukaryotic sequences are likely organellar. Several bacteria have multiple paralogs, but these represent isozymes of signal peptidase I. Virtually all known bacteria may be presumed to A related model finds a simlar protein in many archaea and a few bacteria, as well as a microsomal (endoplasmic reticulum) protein in eukaryotes. [Protein fate, Protein and peptide secretion and trafficking]


Pssm-ID: 274044 [Multi-domain]  Cd Length: 142  Bit Score: 77.65  E-value: 1.94e-18
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  33 VACVARVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIVSLvlltvtpstrqqeiggeeeevekdislaKSPKN 112
Cdd:TIGR02227   2 VFFPYKIPGGSMEPTLKEG-----DRILVNKFAYRTSDPKRGDIVVF----------------------------KDPDT 48

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920 113 PEQKIIKRVIALEGDIVRTI-------GHK-----------------NRYVKVPRGHIWVEGDHHGHSFDSNSFGPVSLG 168
Cdd:TIGR02227  49 NKNIYVKRIIGLPGDKVEFRdgklyinGKKidepylkpngyldtsefNTPVKVPPGHYFVLGDNRDNSLDSRYFGFVPID 128

                         170
                  ....*....|..
gi 1186517920 169 LLHAHATHILWP 180
Cdd:TIGR02227 129 QIIGKVSFVFYP 140
S26_SPase_I cd06530
The S26 Type I signal peptidase (SPase; LepB; leader peptidase B; leader peptidase I; EC 3.4. ...
 36-174 6.63e-18

The S26 Type I signal peptidase (SPase; LepB; leader peptidase B; leader peptidase I; EC 3.4.21.89) family members are essential membrane-bound serine proteases that function to cleave the amino-terminal signal peptide extension from proteins that are translocated across biological membranes. The bacterial signal peptidase I, which is the most intensively studied, has two N-terminal transmembrane segments inserted in the plasma membrane and a hydrophilic, C-terminal catalytic region that is located in the periplasmic space. Although the bacterial signal peptidase I is monomeric, signal peptidases of eukaryotic cells commonly function as oligomeric complexes containing two divergent copies of the catalytic monomer. These are the IMP1 and IMP2 signal peptidases of the mitochondrial inner membrane that remove leader peptides from nuclear- and mitochondrial-encoded proteins. Also, two components of the endoplasmic reticulum signal peptidase in mammals (18-kDa and 21-kDa) belong to this family and they process many proteins that enter the ER for retention or for export to the Golgi apparatus, secretory vesicles, plasma membranes or vacuole. An atypical member of the S26 SPase type I family is the TraF peptidase which has the remarkable activity of producing a cyclic protein of the Pseudomonas pilin system. The type I signal peptidases are unique serine proteases that utilize a serine/lysine catalytic dyad mechanism in place of the classical serine/histidine/aspartic acid catalytic triad mechanism.


Pssm-ID: 119398 [Multi-domain]  Cd Length: 85  Bit Score: 74.54  E-value: 6.63e-18
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  36 VARVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIVSLvlltvtpstrqqeiggeeeevekdislaKSPKNPEQ 115
Cdd:cd06530     2 PVVVPGGSMEPTLQPG-----DLVLVNKLSYGFREPKRGDVVVF----------------------------KSPGDPGK 48

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1186517920 116 KIIKRVIAlegdivrtighknryvkvprghIWVEGDHHGHSFDSNSFGPVSLGLLHAHA 174
Cdd:cd06530    49 PIIKRVIG----------------------YFVLGDNRNNSLDSRYWGPVPEDDIVGKV 85
LepB COG0681
Signal peptidase I [Intracellular trafficking, secretion, and vesicular transport];
1-168 5.32e-12

Signal peptidase I [Intracellular trafficking, secretion, and vesicular transport];


Pssm-ID: 440445 [Multi-domain]  Cd Length: 189  Bit Score: 61.79  E-value: 5.32e-12
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920   1 MAQSQGWvKRYIKAFCKGFFVAVPVAV---TFldrVACVARVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIV 77
Cdd:COG0681     1 MSKKKKK-KRELREWLKSIVIALLLALlirTF---VFEPFVIPSGSMEPTLLVG-----DRLLVNKLSYGFGEPKRGDIV 71

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  78 slVLltvtpstrqqeiggeeeevekdislaKSPKNPEQKIIKRVIALEGDIVR----------------------TIGHK 135
Cdd:COG0681    72 --VF--------------------------KYPEDPSKDYIKRVIGLPGDTVEirdgqvyvngkplnepyleeyyYPVSV 123

                         170       180       190
                  ....*....|....*....|....*....|...
gi 1186517920 136 NRYVKVPRGHIWVEGDHHGHSFDSNSFGPVSLG 168
Cdd:COG0681   124 DGDVEVPPGEEEVPGGGGDNSNDSRSGDPDDGG 156
 
Name Accession Description Interval E-value
Peptidase_S26 pfam10502
Signal peptidase, peptidase S26; This is a family of membrane signal serine endopeptidases ...
 9-179 1.21e-18

Signal peptidase, peptidase S26; This is a family of membrane signal serine endopeptidases which function in the processing of newly-synthesized secreted proteins. Peptidase S26 removes the hydrophobic, N-terminal, signal peptides as proteins are translocated across membranes. The active site residues take the form of a catalytic dyad that is Ser, Lys in subfamily S26A; the Ser is the nucleophile in catalysis, and the Lys is the general base.


Pssm-ID: 431321 [Multi-domain]  Cd Length: 162  Bit Score: 78.79  E-value: 1.21e-18
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920   9 KRYIKAFckgfFVAVPVAVTFldRVACVA--RVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIVslvlltvtp 86
Cdd:pfam10502   2 LEWVKAI----VIALLLALLI--RTFLFEpyVVPGGSMSPTLPIG-----DYLIVNKFSYGLGEPKRGDIV--------- 61

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  87 strqqeiggeeeevekdisLAKSPKNPEQKIIKRVIALEGDIVR---------------------------TIGHKNRYV 139
Cdd:pfam10502  62 -------------------VFRPPEGPGVPLIKRVIGLPGDRVEykddqlyingkpvgepyladrkgrptfDLPPWQGCR 122

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1186517920 140 KVPRGHIWVEGDHHGHSFDSNSFGPVSLGLLHAHATHILW 179
Cdd:pfam10502 123 VVPEGEYFVMGDNRDNSLDSRYFGFVPASNIVGRAVFPVW 162
sigpep_I_bact TIGR02227
signal peptidase I, bacterial type; This model represents signal peptidase I from most ...
 33-180 1.94e-18

signal peptidase I, bacterial type; This model represents signal peptidase I from most bacteria. Eukaryotic sequences are likely organellar. Several bacteria have multiple paralogs, but these represent isozymes of signal peptidase I. Virtually all known bacteria may be presumed to A related model finds a simlar protein in many archaea and a few bacteria, as well as a microsomal (endoplasmic reticulum) protein in eukaryotes. [Protein fate, Protein and peptide secretion and trafficking]


Pssm-ID: 274044 [Multi-domain]  Cd Length: 142  Bit Score: 77.65  E-value: 1.94e-18
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  33 VACVARVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIVSLvlltvtpstrqqeiggeeeevekdislaKSPKN 112
Cdd:TIGR02227   2 VFFPYKIPGGSMEPTLKEG-----DRILVNKFAYRTSDPKRGDIVVF----------------------------KDPDT 48

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920 113 PEQKIIKRVIALEGDIVRTI-------GHK-----------------NRYVKVPRGHIWVEGDHHGHSFDSNSFGPVSLG 168
Cdd:TIGR02227  49 NKNIYVKRIIGLPGDKVEFRdgklyinGKKidepylkpngyldtsefNTPVKVPPGHYFVLGDNRDNSLDSRYFGFVPID 128

                         170
                  ....*....|..
gi 1186517920 169 LLHAHATHILWP 180
Cdd:TIGR02227 129 QIIGKVSFVFYP 140
S26_SPase_I cd06530
The S26 Type I signal peptidase (SPase; LepB; leader peptidase B; leader peptidase I; EC 3.4. ...
 36-174 6.63e-18

The S26 Type I signal peptidase (SPase; LepB; leader peptidase B; leader peptidase I; EC 3.4.21.89) family members are essential membrane-bound serine proteases that function to cleave the amino-terminal signal peptide extension from proteins that are translocated across biological membranes. The bacterial signal peptidase I, which is the most intensively studied, has two N-terminal transmembrane segments inserted in the plasma membrane and a hydrophilic, C-terminal catalytic region that is located in the periplasmic space. Although the bacterial signal peptidase I is monomeric, signal peptidases of eukaryotic cells commonly function as oligomeric complexes containing two divergent copies of the catalytic monomer. These are the IMP1 and IMP2 signal peptidases of the mitochondrial inner membrane that remove leader peptides from nuclear- and mitochondrial-encoded proteins. Also, two components of the endoplasmic reticulum signal peptidase in mammals (18-kDa and 21-kDa) belong to this family and they process many proteins that enter the ER for retention or for export to the Golgi apparatus, secretory vesicles, plasma membranes or vacuole. An atypical member of the S26 SPase type I family is the TraF peptidase which has the remarkable activity of producing a cyclic protein of the Pseudomonas pilin system. The type I signal peptidases are unique serine proteases that utilize a serine/lysine catalytic dyad mechanism in place of the classical serine/histidine/aspartic acid catalytic triad mechanism.


Pssm-ID: 119398 [Multi-domain]  Cd Length: 85  Bit Score: 74.54  E-value: 6.63e-18
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  36 VARVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIVSLvlltvtpstrqqeiggeeeevekdislaKSPKNPEQ 115
Cdd:cd06530     2 PVVVPGGSMEPTLQPG-----DLVLVNKLSYGFREPKRGDVVVF----------------------------KSPGDPGK 48

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 1186517920 116 KIIKRVIAlegdivrtighknryvkvprghIWVEGDHHGHSFDSNSFGPVSLGLLHAHA 174
Cdd:cd06530    49 PIIKRVIG----------------------YFVLGDNRNNSLDSRYWGPVPEDDIVGKV 85
LepB COG0681
Signal peptidase I [Intracellular trafficking, secretion, and vesicular transport];
1-168 5.32e-12

Signal peptidase I [Intracellular trafficking, secretion, and vesicular transport];


Pssm-ID: 440445 [Multi-domain]  Cd Length: 189  Bit Score: 61.79  E-value: 5.32e-12
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920   1 MAQSQGWvKRYIKAFCKGFFVAVPVAV---TFldrVACVARVEGASMQPSLNPGgsqssDVVLLNHWKVRNFEVHRGDIV 77
Cdd:COG0681     1 MSKKKKK-KRELREWLKSIVIALLLALlirTF---VFEPFVIPSGSMEPTLLVG-----DRLLVNKLSYGFGEPKRGDIV 71

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  78 slVLltvtpstrqqeiggeeeevekdislaKSPKNPEQKIIKRVIALEGDIVR----------------------TIGHK 135
Cdd:COG0681    72 --VF--------------------------KYPEDPSKDYIKRVIGLPGDTVEirdgqvyvngkplnepyleeyyYPVSV 123

                         170       180       190
                  ....*....|....*....|....*....|...
gi 1186517920 136 NRYVKVPRGHIWVEGDHHGHSFDSNSFGPVSLG 168
Cdd:COG0681   124 DGDVEVPPGEEEVPGGGGDNSNDSRSGDPDDGG 156
TraF COG4959
Type IV secretory pathway, protease TraF [Posttranslational modification, protein turnover, ...
 113-180 3.05e-10

Type IV secretory pathway, protease TraF [Posttranslational modification, protein turnover, chaperones, Intracellular trafficking, secretion, and vesicular transport];


Pssm-ID: 443985 [Multi-domain]  Cd Length: 114  Bit Score: 55.30  E-value: 3.05e-10
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920 113 PEQKIIKRVIALEGDIVRTIGHK----NRYV--------------------KVPRGHIWVEGDHHGHSFDSNSFGPVSLG 168
Cdd:COG4959    22 RGVPLIKRVAALPGDTVCIKGGQvyinGKPVaealerdragrplpvwqgcgVVPEGEYFLLGDNRPNSFDSRYFGPVPRS 101

                          90
                  ....*....|..
gi 1186517920 169 LLHAHATHILWP 180
Cdd:COG4959   102 QIIGRAVPLWTP 113
Peptidase_S24_S26 cd06462
The S24, S26 LexA/signal peptidase superfamily contains LexA-related and type I signal ...
 36-164 1.44e-07

The S24, S26 LexA/signal peptidase superfamily contains LexA-related and type I signal peptidase families. The S24 LexA protein domains include: the lambda repressor CI/C2 family and related bacterial prophage repressor proteins; LexA (EC 3.4.21.88), the repressor of genes in the cellular SOS response to DNA damage; MucA and the related UmuD proteins, which are lesion-bypass DNA polymerases, induced in response to mitogenic DNA damage; RulA, a component of the rulAB locus that confers resistance to UV, and RuvA, which is a component of the RuvABC resolvasome that catalyzes the resolution of Holliday junctions that arise during genetic recombination and DNA repair. The S26 type I signal peptidase (SPase) family also includes mitochondrial inner membrane protease (IMP)-like members. SPases are essential membrane-bound proteases which function to cleave away the amino-terminal signal peptide from the translocated pre-protein, thus playing a crucial role in the transport of proteins across membranes in all living organisms. All members in this superfamily are unique serine proteases that carry out catalysis using a serine/lysine dyad instead of the prototypical serine/histidine/aspartic acid triad found in most serine proteases.


Pssm-ID: 119396 [Multi-domain]  Cd Length: 84  Bit Score: 47.26  E-value: 1.44e-07
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  36 VARVEGASMQPSLNPGgsqssDVVLLNHWKvrnFEVHRGDIVslvlltvtpstrqqeiggeeeevekdisLAKSPKNpeQ 115
Cdd:cd06462     2 ALRVEGDSMEPTIPDG-----DLVLVDKSS---YEPKRGDIV----------------------------VFRLPGG--E 43

                          90       100       110       120
                  ....*....|....*....|....*....|....*....|....*....
gi 1186517920 116 KIIKRVIALEGDivrtighknryvkvprGHIWVEGDHHgHSFDSNSFGP 164
Cdd:cd06462    44 LTVKRVIGLPGE----------------GHYFLLGDNP-NSPDSRIDGP 75
sod_Ni_protease TIGR02754
nickel-type superoxide dismutase maturation protease; Members of this protein family are ...
 37-170 1.67e-04

nickel-type superoxide dismutase maturation protease; Members of this protein family are apparent proteases encoded adjacent to the genes for a nickel-type superoxide dismutase. This family belongs to the same larger family (see pfam00717) as signal peptidase I, an unusual serine protease suggested to have a Ser/Lys catalytic dyad. [Cellular processes, Detoxification, Protein fate, Protein modification and repair]


Pssm-ID: 274282 [Multi-domain]  Cd Length: 90  Bit Score: 38.97  E-value: 1.67e-04
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1186517920  37 ARVEGASMQPSLNPGgsqssDVVLLNHWkVRNFEV-HRGDIVslvlltvtpstrqqeiggeeeevekdisLAKSPKNPEQ 115
Cdd:TIGR02754   1 AKVTGVSMSPTLPPG-----DRIIVVPW-LKIFRVpPIGNVV----------------------------VVRHPLQPYG 46

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*
gi 1186517920 116 KIIKRVIAlegdivrtighknryvkVPRGHIWVEGDHHGHSFDSNSFGPVSLGLL 170
Cdd:TIGR02754  47 LIIKRLAA-----------------VDDNGLFLLGDNPKASTDSRQLGPVPRSLL 84
 
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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