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Conserved domains on  [gi|158534355|gb|ABW71936|]
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cytochrome oxidase subunit I, partial (mitochondrion) [Nycticebus coucang]

Protein Classification

heme-copper oxidase family protein( domain architecture ID 14)

heme-copper oxidase family protein may catalyze the transfer of electrons from an electron donor onto molecular oxygen

Graphical summary

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List of domain hits

 Name Accession Description Interval E-value
Heme_Cu_Oxidase_I super family cl00275
Heme-copper oxidase subunit I. Heme-copper oxidases are transmembrane protein complexes in ...
 1-197 5.26e-141

Heme-copper oxidase subunit I. Heme-copper oxidases are transmembrane protein complexes in the respiratory chains of prokaryotes and mitochondria which catalyze the reduction of O2 and simultaneously pump protons across the membrane. The superfamily is diverse in terms of electron donors, subunit composition, and heme types. The number of subunits varies from three to five in bacteria and up to 13 in mammalian mitochondria. It has been proposed that Archaea acquired heme-copper oxidases through gene transfer from Gram-positive bacteria. Membership in the superfamily is defined by subunit I, which contains a heme-copper binuclear center (the active site where O2 is reduced to water) formed by a high-spin heme and a copper ion. It also contains a low-spin heme, believed to participate in the transfer of electrons to the binuclear center. Only subunit I is common to the entire superfamily. For every reduction of an O2 molecule, eight protons are taken from the inside aqueous compartment and four electrons are taken from the electron donor on the opposite side of the membrane. The four electrons and four of the protons are used in the reduction of O2; the four remaining protons are pumped across the membrane. This charge separation of four charges contributes to the electrochemical gradient used for ATP synthesis. Two proton channels, the D-pathway and K-pathway, leading to the binuclear center have been identified in subunit I of cytochrome c oxidase (CcO) and ubiquinol oxidase. A well-defined pathway for the transfer of pumped protons beyond the binuclear center has not been identified. Electron transfer occurs in two segments: from the electron donor to the low-spin heme, and from the low-spin heme to the binuclear center. The first segment can be a multi-step process and varies among the different families, while the second segment, a direct transfer, is consistent throughout the superfamily.


The actual alignment was detected with superfamily member MTH00116:

Pssm-ID: 469701  Cd Length: 515  Bit Score: 402.93  E-value: 5.26e-141
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00116  32 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00116 112 LLASSTVEAGAGTGWTVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGAINFITTCINMKPPAMSQYQTPLFVWSVLIT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00116 192 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
 
Name Accession Description Interval E-value
COX1 MTH00116
cytochrome c oxidase subunit I; Provisional
 1-197 5.26e-141

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177177  Cd Length: 515  Bit Score: 402.93  E-value: 5.26e-141
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00116  32 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00116 112 LLASSTVEAGAGTGWTVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGAINFITTCINMKPPAMSQYQTPLFVWSVLIT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00116 192 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
Cyt_c_Oxidase_I cd01663
Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the ...
 1-197 1.19e-113

Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the respiratory chains of eukaryotes and most bacteria, is a multi-chain transmembrane protein located in the inner membrane of mitochondria and the cell membrane of prokaryotes. It catalyzes the reduction of O2 and simultaneously pumps protons across the membrane. The number of subunits varies from three to five in bacteria and up to 13 in mammalian mitochondria. Only subunits I and II are essential for function, but subunit III, which is also conserved, may play a role in assembly or oxygen delivery to the active site. Subunits I, II, and III of mammalian CcO are encoded within the mitochondrial genome and the remaining 10 subunits are encoded within the nuclear genome. Subunit I contains a heme-copper binuclear center (the active site where O2 is reduced to water) formed by a high-spin heme (heme a3) and a copper ion (CuB). It also contains a low-spin heme (heme a), believed to participate in the transfer of electrons to the binuclear center. For every reduction of an O2 molecule, eight protons are taken from the inside aqueous compartment and four electrons are taken from cytochrome c on the opposite side of the membrane. The four electrons and four of the protons are used in the reduction of O2; the four remaining protons are pumped across the membrane. This charge separation of four charges contributes to the electrochemical gradient used for ATP synthesis. Two proton channels, the D-pathway and K-pathway, leading to the binuclear center have been identified in subunit I. A well-defined pathway for the transfer of pumped protons beyond the binuclear center has not been identified. Electrons are transferred from cytochrome c (the electron donor) to heme a via the CuA binuclear site in subunit II, and directly from heme a to the binuclear center.


Pssm-ID: 238833  Cd Length: 488  Bit Score: 332.14  E-value: 1.19e-113
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:cd01663   23 SLSLLIRLELSQPGSQLGNDQLYNVIVTAHALIMIFFMVMPALIGGFGNWLVPLMIGAPDMAFPRLNNLSFWLLPPSLLL 102

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:cd01663  103 LLLSALVEGGAGTGWTVYPPLSSILAHSGPSVDLAIFSLHLAGISSILGAINFITTIFNMRAPGMTLEKMPLFVWSVLIT 182

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:cd01663  183 AFLLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 219
CyoB COG0843
Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];
1-197 1.31e-60

Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];


Pssm-ID: 440605  Cd Length: 535  Bit Score: 197.27  E-value: 1.31e-60
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:COG0843   35 LLALLMRLQLAGPGLGLLSPETYNQLFTMHGTIMIFFFATP-FLAGFGNYLVPLQIGARDMAFPRLNALSFWLYLFGGLL 113

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:COG0843  114 LLISLFVGGAADVGWTFYPPLSGLEASPGVGVDLWLLGLALFGVGSILGGVNFIVTILKMRAPGMTLMRMPLFTWAALVT 193

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:COG0843  194 SILILLAFPVLAAALLLLLLDRSLGTHFFDPAGGGDP 230
COX1 pfam00115
Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key ...
 1-192 1.84e-37

Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key enzyme in aerobic metabolism. Proton pumping haem-copper oxidases represent the terminal, energy-transfer enzymes of respiratory chains in prokaryotes and eukaryotes. The CuB-haem a3 (or haem o) binuclear centre, associated with the largest subunit I of cytochrome c and ubiquinol oxidases (E.C:1.10.3.11), is directly involved in the coupling between dioxygen reduction and proton pumping. Some terminal oxidases generate a transmembrane proton gradient across the plasma membrane (prokaryotes) or the mitochondrial inner membrane (eukaryotes). The enzyme complex consists of 3-4 subunits (prokaryotes) up to 13 polypeptides (mammals) of which only the catalytic subunit (equivalent to mammalian subunit I (COXI) is found in all haem-copper respiratory oxidases. The presence of a bimetallic centre (formed by a high-spin haem and copper B) as well as a low-spin haem, both ligated to six conserved histidine residues near the outer side of four transmembrane spans within CO I is common to all family members.


Pssm-ID: 459678  Cd Length: 432  Bit Score: 134.24  E-value: 1.84e-37
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355    1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:pfam00115  19 LLGLLIRLQLAFPGLNFLSPLTYNQLRTLHGNLMIFWFATP-FLFGFGNYLVPLMIGARDMAFPRLNALSFWLVVLGAVL 97

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   81 LLASSMveaGAGTGWTVYPPLAGnlahagasVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQyQTPLFVWSVMIT 160
Cdd:pfam00115  98 LLASFG---GATTGWTEYPPLVG--------VDLWYIGLLLAGVSSLLGAINFIVTILKRRAPGMTL-RMPLFVWAILAT 165

                         170       180       190
                  ....*....|....*....|....*....|..
gi 158534355  161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPA 192
Cdd:pfam00115 166 AILILLAFPVLAAALLLLLLDRSLGAGGGDPL 197
QoxB TIGR02882
cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type ...
 3-197 3.05e-34

cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type quinone oxidase, one of several bacterial terminal oxidases. This complex couples oxidation of reduced quinones with the reduction of molecular oxygen to water and the pumping of protons to form a proton gradient utilized for ATP production. aa3-type oxidases contain two heme a cofactors as well as copper atoms in the active site. [Energy metabolism, Electron transport]


Pssm-ID: 131928  Cd Length: 643  Bit Score: 127.66  E-value: 3.05e-34
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355    3 SLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLLLL 82
Cdd:TIGR02882  72 ALLMRAQLTVPDNKFLDAQHYNEIFTTHGVIMIIFMAMPFIIG-LMNIVVPLQIGARDVAFPVLNALSFWLFFAGAMLFN 150

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   83 ASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMITAV 162
Cdd:TIGR02882 151 ISFVIGGSPDAGWTNYAPLAGPEFSPGVGVNYYLIALQISGIGTLMTGINFFVTILKMRAPGMKLMQMPMFTWTTLITTL 230

                         170       180       190
                  ....*....|....*....|....*....|....*
gi 158534355  163 LLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:TIGR02882 231 IIIFAFPVLTVALALMTTDRIFDTAFFTVAHGGMP 265
 
Name Accession Description Interval E-value
COX1 MTH00116
cytochrome c oxidase subunit I; Provisional
 1-197 5.26e-141

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177177  Cd Length: 515  Bit Score: 402.93  E-value: 5.26e-141
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00116  32 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00116 112 LLASSTVEAGAGTGWTVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGAINFITTCINMKPPAMSQYQTPLFVWSVLIT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00116 192 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00103
cytochrome c oxidase subunit I; Validated
 1-197 2.52e-129

cytochrome c oxidase subunit I; Validated


Pssm-ID: 177165  Cd Length: 513  Bit Score: 373.06  E-value: 2.52e-129
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00103  32 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00103 112 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAMSQYQTPLFVWSVLIT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00103 192 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00077
cytochrome c oxidase subunit I; Provisional
 1-197 2.00e-127

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214419  Cd Length: 514  Bit Score: 368.50  E-value: 2.00e-127
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00077  32 ALSLLIRAELSQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00077 112 LLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTSINMKPPSMSQYQTPLFVWSVLIT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00077 192 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00153
cytochrome c oxidase subunit I; Provisional
 1-197 6.60e-123

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177210  Cd Length: 511  Bit Score: 356.49  E-value: 6.60e-123
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00153  30 SLSLLIRAELGQPGSLIGDDQIYNVIVTAHAFIMIFFMVMPIMIGGFGNWLVPLMLGAPDMAFPRMNNMSFWLLPPSLTL 109

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00153 110 LLSSSMVESGAGTGWTVYPPLSSNIAHSGASVDLAIFSLHLAGISSILGAINFITTIINMRSKGMTLDRMPLFVWSVLIT 189

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00153 190 AILLLLSLPVLAGAITMLLTDRNLNTSFFDPAGGGDP 226
COX1 MTH00167
cytochrome c oxidase subunit I; Provisional
 1-197 3.41e-116

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177222  Cd Length: 512  Bit Score: 339.73  E-value: 3.41e-116
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00167  32 ALSLLIRAELSQPGSLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSLLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00167 112 LLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGSINFITTIINMKPPGITQYQTPLFVWSILVT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00167 192 TILLLLSLPVLAAAITMLLTDRNLNTTFFDPAGGGDP 228
Cyt_c_Oxidase_I cd01663
Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the ...
 1-197 1.19e-113

Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the respiratory chains of eukaryotes and most bacteria, is a multi-chain transmembrane protein located in the inner membrane of mitochondria and the cell membrane of prokaryotes. It catalyzes the reduction of O2 and simultaneously pumps protons across the membrane. The number of subunits varies from three to five in bacteria and up to 13 in mammalian mitochondria. Only subunits I and II are essential for function, but subunit III, which is also conserved, may play a role in assembly or oxygen delivery to the active site. Subunits I, II, and III of mammalian CcO are encoded within the mitochondrial genome and the remaining 10 subunits are encoded within the nuclear genome. Subunit I contains a heme-copper binuclear center (the active site where O2 is reduced to water) formed by a high-spin heme (heme a3) and a copper ion (CuB). It also contains a low-spin heme (heme a), believed to participate in the transfer of electrons to the binuclear center. For every reduction of an O2 molecule, eight protons are taken from the inside aqueous compartment and four electrons are taken from cytochrome c on the opposite side of the membrane. The four electrons and four of the protons are used in the reduction of O2; the four remaining protons are pumped across the membrane. This charge separation of four charges contributes to the electrochemical gradient used for ATP synthesis. Two proton channels, the D-pathway and K-pathway, leading to the binuclear center have been identified in subunit I. A well-defined pathway for the transfer of pumped protons beyond the binuclear center has not been identified. Electrons are transferred from cytochrome c (the electron donor) to heme a via the CuA binuclear site in subunit II, and directly from heme a to the binuclear center.


Pssm-ID: 238833  Cd Length: 488  Bit Score: 332.14  E-value: 1.19e-113
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:cd01663   23 SLSLLIRLELSQPGSQLGNDQLYNVIVTAHALIMIFFMVMPALIGGFGNWLVPLMIGAPDMAFPRLNNLSFWLLPPSLLL 102

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:cd01663  103 LLLSALVEGGAGTGWTVYPPLSSILAHSGPSVDLAIFSLHLAGISSILGAINFITTIFNMRAPGMTLEKMPLFVWSVLIT 182

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:cd01663  183 AFLLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 219
COX1 MTH00183
cytochrome c oxidase subunit I; Provisional
 1-197 2.96e-110

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177234  Cd Length: 516  Bit Score: 324.57  E-value: 2.96e-110
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00183  32 ALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00183 112 LLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAISQYQTPLFVWAVLIT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00183 192 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00142
cytochrome c oxidase subunit I; Provisional
 1-197 5.68e-107

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214431  Cd Length: 511  Bit Score: 315.89  E-value: 5.68e-107
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00142  30 GLSLLIRAELGQPGSLLGDDQLYNVIVTAHAFVMIFFMVMPVMIGGFGNWLVPLMLGAPDMAFPRMNNMSFWLLPPALLL 109

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00142 110 LLSSAAVESGAGTGWTVYPPLSSNLAHSGGSVDLAIFSLHLAGVSSILGAINFITTVINMRAGGMKFERVPLFVWSVKIT 189

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00142 190 AILLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 226
COX1 MTH00223
cytochrome c oxidase subunit I; Provisional
 1-197 4.27e-106

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177260  Cd Length: 512  Bit Score: 313.84  E-value: 4.27e-106
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00223  29 SLSLLIRAELGQPGALLGDDQLYNVIVTAHAFVMIFFLVMPMMIGGFGNWLVPLMLGAPDMAFPRLNNMSFWLLPPSLYL 108

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00223 109 LLSSSAVESGVGTGWTVYPPLSSNLAHAGPSVDLAIFSLHLAGVSSILGAINFITTIINMRSPGMQLERLPLFVWSVKVT 188

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00223 189 AFLLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 225
COX1 MTH00037
cytochrome c oxidase subunit I; Provisional
 1-197 4.24e-94

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177112  Cd Length: 517  Bit Score: 283.26  E-value: 4.24e-94
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00037  32 AMSVIIRTELAQPGSLLQDDQIYNVIVTAHALVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLIPPSFLL 111

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00037 112 LLASAGVESGAGTGWTIYPPLSSNIAHAGGSVDLAIFSLHLAGASSILASINFITTIINMRTPGMTFDRLPLFVWSVFIT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00037 192 AFLLLLSLPVLAGAITMLLTDRNINTTFFDPAGGGDP 228
COX1 MTH00007
cytochrome c oxidase subunit I; Validated
 1-197 4.07e-92

cytochrome c oxidase subunit I; Validated


Pssm-ID: 133649  Cd Length: 511  Bit Score: 277.94  E-value: 4.07e-92
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00007  29 SMSLLIRIELGQPGAFLGSDQLYNTIVTAHAFLMIFFLVMPVFIGGFGNWLVPLMLGAPDMAFPRLNNMSFWLLPPALIL 108

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00007 109 LVSSAAVEKGVGTGWTVYPPLASNLAHAGPSVDLAIFSLHLAGVSSILGAINFITTVINMRWKGLRLERIPLFVWAVVIT 188

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00007 189 VVLLLLSLPVLAGAITMLLTDRNLNTSFFDPAGGGDP 225
COX1 MTH00182
cytochrome c oxidase subunit I; Provisional
 1-197 1.06e-88

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214451  Cd Length: 525  Bit Score: 269.77  E-value: 1.06e-88
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00182  34 AFSMLIRLELSAPGAMLGDDHLYNVIVTAHAFIMIFFLVMPVMIGGFGNWLVPLYIGAPDMAFPRLNNISFWLLPPALIL 113

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00182 114 LLGSAFVEQGAGTGWTVYPPLSSIQAHSGGAVDMAIFSLHLAGVSSILGAINFITTIFNMRAPGVTFNRLPLFVWSILIT 193

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00182 194 AFLLLLSLPVLAGAITMLLTDRNFNTTFFDPAGGGDP 230
COX1 MTH00184
cytochrome c oxidase subunit I; Provisional
 1-197 3.46e-87

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177235  Cd Length: 519  Bit Score: 265.54  E-value: 3.46e-87
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00184  34 AFSMLIRLELSAPGSMLGDDHLYNVIVTAHAFVMIFFLVMPVMIGGFGNWFVPLYIGAPDMAFPRLNNISFWLLPPALTL 113

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00184 114 LLGSAFVEQGAGTGWTVYPPLSSIQAHSGGSVDMAIFSLHLAGISSILGAMNFITTIFNMRAPGITMDRMPLFVWSILVT 193

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00184 194 TFLLLLSLPVLAGAITMLLTDRNFNTTFFDPAGGGDP 230
COX1 MTH00079
cytochrome c oxidase subunit I; Provisional
 1-197 1.17e-81

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177148  Cd Length: 508  Bit Score: 251.14  E-value: 1.17e-81
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00079  33 SLSLIIRLELSKPGLLLGNGQLYNSVITAHAILMIFFMVMPSMIGGFGNWMLPLMLGAPDMSFPRLNNLSFWLLPTSLFL 112

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAgNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00079 113 ILDSCFVDMGPGTSWTVYPPLS-TLGHPGSSVDLAIFSLHCAGISSILGGINFMVTTKNLRSSSISLEHMSLFVWTVFVT 191

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00079 192 VFLLVLSLPVLAGAITMLLTDRNLNTSFFDPSTGGNP 228
COX1 MTH00026
cytochrome c oxidase subunit I; Provisional
 1-197 1.09e-80

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 164599  Cd Length: 534  Bit Score: 249.55  E-value: 1.09e-80
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:MTH00026  33 AFSMLIRLELSSPGSMLGDDHLYNVIVTAHAFVMIFFLVMPTMIGGFGNWFVPLMIGAPDMAFPRLNNISFWLLPPALFL 112

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:MTH00026 113 LLGSSLVEQGAGTGWTVYPPLASIQAHSGGSVDMAIFSLHLAGLSSILGAMNFITTVMNMRTPGMTMSRIPLFVWSVFIT 192

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00026 193 AILLLLSLPVLAGAITMLLTDRNFNTTFFDPAGGGDP 229
Heme_Cu_Oxidase_I cd00919
Heme-copper oxidase subunit I. Heme-copper oxidases are transmembrane protein complexes in ...
 1-197 4.59e-70

Heme-copper oxidase subunit I. Heme-copper oxidases are transmembrane protein complexes in the respiratory chains of prokaryotes and mitochondria which catalyze the reduction of O2 and simultaneously pump protons across the membrane. The superfamily is diverse in terms of electron donors, subunit composition, and heme types. The number of subunits varies from three to five in bacteria and up to 13 in mammalian mitochondria. It has been proposed that Archaea acquired heme-copper oxidases through gene transfer from Gram-positive bacteria. Membership in the superfamily is defined by subunit I, which contains a heme-copper binuclear center (the active site where O2 is reduced to water) formed by a high-spin heme and a copper ion. It also contains a low-spin heme, believed to participate in the transfer of electrons to the binuclear center. Only subunit I is common to the entire superfamily. For every reduction of an O2 molecule, eight protons are taken from the inside aqueous compartment and four electrons are taken from the electron donor on the opposite side of the membrane. The four electrons and four of the protons are used in the reduction of O2; the four remaining protons are pumped across the membrane. This charge separation of four charges contributes to the electrochemical gradient used for ATP synthesis. Two proton channels, the D-pathway and K-pathway, leading to the binuclear center have been identified in subunit I of cytochrome c oxidase (CcO) and ubiquinol oxidase. A well-defined pathway for the transfer of pumped protons beyond the binuclear center has not been identified. Electron transfer occurs in two segments: from the electron donor to the low-spin heme, and from the low-spin heme to the binuclear center. The first segment can be a multi-step process and varies among the different families, while the second segment, a direct transfer, is consistent throughout the superfamily.


Pssm-ID: 238461  Cd Length: 463  Bit Score: 220.09  E-value: 4.59e-70
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPlMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:cd00919   21 LLALLIRLELATPGSLFLDPQLYNQLVTAHGVIMIFFFVMPAIFGGFGNLLPP-LIGARDLAFPRLNNLSFWLFPPGLLL 99

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:cd00919  100 LLSSVLVGGGAGTGWTFYPPLSTLSYSSGVGVDLAILGLHLAGVSSILGAINFITTILNMRAPGMTLDKMPLFVWSVLVT 179

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:cd00919  180 AILLLLALPVLAAALVMLLLDRNFGTSFFDPAGGGDP 216
CyoB COG0843
Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];
1-197 1.31e-60

Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];


Pssm-ID: 440605  Cd Length: 535  Bit Score: 197.27  E-value: 1.31e-60
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:COG0843   35 LLALLMRLQLAGPGLGLLSPETYNQLFTMHGTIMIFFFATP-FLAGFGNYLVPLQIGARDMAFPRLNALSFWLYLFGGLL 113

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:COG0843  114 LLISLFVGGAADVGWTFYPPLSGLEASPGVGVDLWLLGLALFGVGSILGGVNFIVTILKMRAPGMTLMRMPLFTWAALVT 193

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:COG0843  194 SILILLAFPVLAAALLLLLLDRSLGTHFFDPAGGGDP 230
COX1 MTH00048
cytochrome c oxidase subunit I; Provisional
 2-197 5.96e-52

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177123  Cd Length: 511  Bit Score: 174.10  E-value: 5.96e-52
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   2 LSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLLL 81
Cdd:MTH00048  34 LSLLIRLNFLDPYYNVISLDVYNFLITNHGIIMIFFFLMPVLIGGFGNYLLPLLLGLSDLNLPRLNALSAWLLVPSIVFL 113

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  82 LASSMVeaGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSqYQTPLFVWSVMITA 161
Cdd:MTH00048 114 LLSMCL--GAGVGWTFYPPLSSSLFSSSWGVDFLMFSLHLAGVSSLFGSINFICTIYSAFMTNVF-SRTSIILWSYLFTS 190

                        170       180       190
                 ....*....|....*....|....*....|....*.
gi 158534355 162 VLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:MTH00048 191 ILLLLSLPVLAAAITMLLFDRNFGSAFFDPLGGGDP 226
Ubiquinol_Oxidase_I cd01662
Ubiquinol oxidase subunit I. Ubiquinol oxidase, the terminal oxidase in the respiratory ...
 1-197 6.48e-51

Ubiquinol oxidase subunit I. Ubiquinol oxidase, the terminal oxidase in the respiratory chains of aerobic bacteria, is a multi-chain transmembrane protein located in the cell membrane. It catalyzes the reduction of O2 and simultaneously pumps protons across the membrane. The number of subunits in ubiquinol oxidase varies from two to five. Subunit I contains a heme-copper binuclear center (the active site where O2 is reduced to water) formed by a high-spin heme and a copper ion. It also contains a low-spin heme, believed to participate in the transfer of electrons from ubiquinol to the binuclear center. For every reduction of an O2 molecule, eight protons are taken from the inside aqueous compartment and four electrons are taken from ubiquinol on the opposite side of the membrane. The four electrons and four of the protons are used in the reduction of O2; the four remaining protons are pumped across the membrane. This charge separation of four charges contributes to the electrochemical gradient used for ATP synthesis. Two proton channels, the D-pathway and K-pathway, leading to the binuclear center have been identified in subunit I. It is generally believed that the channels contain water molecules that act as 'proton wires' to transfer the protons. A well-defined pathway for the transfer of pumped protons beyond the binuclear center has not been identified. Electrons are believed to be transferred directly from ubiquinol (the electron donor) to the low-spin heme, and directly from the low-spin heme to the binuclear center.


Pssm-ID: 238832  Cd Length: 501  Bit Score: 170.84  E-value: 6.48e-51
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:cd01662   27 VDALLMRTQLALPGNDFLSPEHYNQIFTMHGTIMIFLFAMPLVFG-LMNYLVPLQIGARDVAFPRLNALSFWLFLFGGLL 105

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  81 LLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMIT 160
Cdd:cd01662  106 LNASLLIGGFPDAGWFAYPPLSGLEYSPGVGVDYWILGLQFSGIGTLLGAINFIVTILKMRAPGMTLMRMPIFTWTTLVT 185

                        170       180       190
                 ....*....|....*....|....*....|....*..
gi 158534355 161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:cd01662  186 SILILFAFPVLTAALALLELDRYFGTHFFTNALGGNP 222
COX1 pfam00115
Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key ...
 1-192 1.84e-37

Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key enzyme in aerobic metabolism. Proton pumping haem-copper oxidases represent the terminal, energy-transfer enzymes of respiratory chains in prokaryotes and eukaryotes. The CuB-haem a3 (or haem o) binuclear centre, associated with the largest subunit I of cytochrome c and ubiquinol oxidases (E.C:1.10.3.11), is directly involved in the coupling between dioxygen reduction and proton pumping. Some terminal oxidases generate a transmembrane proton gradient across the plasma membrane (prokaryotes) or the mitochondrial inner membrane (eukaryotes). The enzyme complex consists of 3-4 subunits (prokaryotes) up to 13 polypeptides (mammals) of which only the catalytic subunit (equivalent to mammalian subunit I (COXI) is found in all haem-copper respiratory oxidases. The presence of a bimetallic centre (formed by a high-spin haem and copper B) as well as a low-spin haem, both ligated to six conserved histidine residues near the outer side of four transmembrane spans within CO I is common to all family members.


Pssm-ID: 459678  Cd Length: 432  Bit Score: 134.24  E-value: 1.84e-37
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355    1 ALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLL 80
Cdd:pfam00115  19 LLGLLIRLQLAFPGLNFLSPLTYNQLRTLHGNLMIFWFATP-FLFGFGNYLVPLMIGARDMAFPRLNALSFWLVVLGAVL 97

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   81 LLASSMveaGAGTGWTVYPPLAGnlahagasVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQyQTPLFVWSVMIT 160
Cdd:pfam00115  98 LLASFG---GATTGWTEYPPLVG--------VDLWYIGLLLAGVSSLLGAINFIVTILKRRAPGMTL-RMPLFVWAILAT 165

                         170       180       190
                  ....*....|....*....|....*....|..
gi 158534355  161 AVLLLLSLPVLAAGITMLLTDRNLNTTFFDPA 192
Cdd:pfam00115 166 AILILLAFPVLAAALLLLLLDRSLGAGGGDPL 197
QoxB TIGR02882
cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type ...
 3-197 3.05e-34

cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type quinone oxidase, one of several bacterial terminal oxidases. This complex couples oxidation of reduced quinones with the reduction of molecular oxygen to water and the pumping of protons to form a proton gradient utilized for ATP production. aa3-type oxidases contain two heme a cofactors as well as copper atoms in the active site. [Energy metabolism, Electron transport]


Pssm-ID: 131928  Cd Length: 643  Bit Score: 127.66  E-value: 3.05e-34
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355    3 SLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLLLL 82
Cdd:TIGR02882  72 ALLMRAQLTVPDNKFLDAQHYNEIFTTHGVIMIIFMAMPFIIG-LMNIVVPLQIGARDVAFPVLNALSFWLFFAGAMLFN 150

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355   83 ASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMITAV 162
Cdd:TIGR02882 151 ISFVIGGSPDAGWTNYAPLAGPEFSPGVGVNYYLIALQISGIGTLMTGINFFVTILKMRAPGMKLMQMPMFTWTTLITTL 230

                         170       180       190
                  ....*....|....*....|....*....|....*
gi 158534355  163 LLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 197
Cdd:TIGR02882 231 IIIFAFPVLTVALALMTTDRIFDTAFFTVAHGGMP 265
PRK15017 PRK15017
cytochrome o ubiquinol oxidase subunit I; Provisional
 23-196 6.01e-33

cytochrome o ubiquinol oxidase subunit I; Provisional


Pssm-ID: 184978  Cd Length: 663  Bit Score: 123.89  E-value: 6.01e-33
                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355  23 YNVIVTAHAFVMIFFMVMPIMIGgFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSMVEAGAGTGWTVYPPLA 102
Cdd:PRK15017  99 YDQIFTAHGVIMIFFVAMPFVIG-LMNLVVPLQIGARDVAFPFLNNLSFWFTVVGVILVNVSLGVGEFAQTGWLAYPPLS 177

                         90       100       110       120       130       140       150       160
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 158534355 103 GNLAHAGASVDLTIFSLHLAGVSSILGAINFITTAINMKPPAMSQYQTPLFVWSVMITAVLLLLSLPVLAAGITMLLTDR 182
Cdd:PRK15017 178 GIEYSPGVGVDYWIWSLQLSGIGTTLTGINFFVTILKMRAPGMTMFKMPVFTWASLCANVLIIASFPILTVTVALLTLDR 257

                        170
                 ....*....|....
gi 158534355 183 NLNTTFFDPAGGGD 196
Cdd:PRK15017 258 YLGTHFFTNDMGGN 271
 
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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