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Conserved domains on  [gi|1852012659|gb|QKO01933|]
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cytochrome c oxidase subunit I, partial (mitochondrion) [Synodus sp. XS-17]

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 ...
 1-200 1.24e-131

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 MTH00183:

Pssm-ID: 469701  Cd Length: 516  Bit Score: 379.27  E-value: 1.24e-131
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00183   29 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00183  109 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAISQYQTPLFVWAV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00183  189 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
 
Name Accession Description Interval E-value
COX1 MTH00183
cytochrome c oxidase subunit I; Provisional
 1-200 1.24e-131

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177234  Cd Length: 516  Bit Score: 379.27  E-value: 1.24e-131
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00183   29 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00183  109 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAISQYQTPLFVWAV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00183  189 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
Cyt_c_Oxidase_I cd01663
Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the ...
 1-200 7.72e-116

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: 337.92  E-value: 7.72e-116
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:cd01663    20 VGTSLSLLIRLELSQPGSQLGNDQLYNVIVTAHALIMIFFMVMPALIGGFGNWLVPLMIGAPDMAFPRLNNLSFWLLPPS 99

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:cd01663   100 LLLLLLSALVEGGAGTGWTVYPPLSSILAHSGPSVDLAIFSLHLAGISSILGAINFITTIFNMRAPGMTLEKMPLFVWSV 179

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:cd01663   180 LITAFLLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 219
CyoB COG0843
Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];
1-200 1.67e-62

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


Pssm-ID: 440605  Cd Length: 535  Bit Score: 202.28  E-value: 1.67e-62
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:COG0843    32 IGGLLALLMRLQLAGPGLGLLSPETYNQLFTMHGTIMIFFFATP-FLAGFGNYLVPLQIGARDMAFPRLNALSFWLYLFG 110

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:COG0843   111 GLLLLISLFVGGAADVGWTFYPPLSGLEASPGVGVDLWLLGLALFGVGSILGGVNFIVTILKMRAPGMTLMRMPLFTWAA 190

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:COG0843   191 LVTSILILLAFPVLAAALLLLLLDRSLGTHFFDPAGGGDP 230
COX1 pfam00115
Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key ...
 1-195 4.66e-40

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: 141.17  E-value: 4.66e-40
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:pfam00115  16 VGGLLGLLIRLQLAFPGLNFLSPLTYNQLRTLHGNLMIFWFATP-FLFGFGNYLVPLMIGARDMAFPRLNALSFWLVVLG 94

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGveaGAGTGWTVYPPLAGnlahagasVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQyQTPLFVWAV 160
Cdd:pfam00115  95 AVLLLASFG---GATTGWTEYPPLVG--------VDLWYIGLLLAGVSSLLGAINFIVTILKRRAPGMTL-RMPLFVWAI 162

                         170       180       190
                  ....*....|....*....|....*....|....*
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPA 195
Cdd:pfam00115 163 LATAILILLAFPVLAAALLLLLLDRSLGAGGGDPL 197
QoxB TIGR02882
cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type ...
 2-200 6.47e-35

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: 129.59  E-value: 6.47e-35
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   2 GTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSF 81
Cdd:TIGR02882  68 GGIDALLMRAQLTVPDNKFLDAQHYNEIFTTHGVIMIIFMAMPFIIG-LMNIVVPLQIGARDVAFPVLNALSFWLFFAGA 146

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  82 LLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAVL 161
Cdd:TIGR02882 147 MLFNISFVIGGSPDAGWTNYAPLAGPEFSPGVGVNYYLIALQISGIGTLMTGINFFVTILKMRAPGMKLMQMPMFTWTTL 226

                         170       180       190
                  ....*....|....*....|....*....|....*....
gi 1852012659 162 ITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:TIGR02882 227 ITTLIIIFAFPVLTVALALMTTDRIFDTAFFTVAHGGMP 265
 
Name Accession Description Interval E-value
COX1 MTH00183
cytochrome c oxidase subunit I; Provisional
 1-200 1.24e-131

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177234  Cd Length: 516  Bit Score: 379.27  E-value: 1.24e-131
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00183   29 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00183  109 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAISQYQTPLFVWAV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00183  189 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00077
cytochrome c oxidase subunit I; Provisional
 1-200 2.43e-130

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214419  Cd Length: 514  Bit Score: 375.82  E-value: 2.43e-130
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00077   29 VGTALSLLIRAELSQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00077  109 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTSINMKPPSMSQYQTPLFVWSV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00077  189 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00153
cytochrome c oxidase subunit I; Provisional
 1-200 4.75e-124

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177210  Cd Length: 511  Bit Score: 359.57  E-value: 4.75e-124
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00153   27 VGTSLSLLIRAELGQPGSLIGDDQIYNVIVTAHAFIMIFFMVMPIMIGGFGNWLVPLMLGAPDMAFPRMNNMSFWLLPPS 106

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00153  107 LTLLLSSSMVESGAGTGWTVYPPLSSNIAHSGASVDLAIFSLHLAGISSILGAINFITTIINMRSKGMTLDRMPLFVWSV 186

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00153  187 LITAILLLLSLPVLAGAITMLLTDRNLNTSFFDPAGGGDP 226
COX1 MTH00116
cytochrome c oxidase subunit I; Provisional
 1-200 2.36e-122

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177177  Cd Length: 515  Bit Score: 355.55  E-value: 2.36e-122
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00116   29 VGTALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00116  109 FLLLLASSTVEAGAGTGWTVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGAINFITTCINMKPPAMSQYQTPLFVWSV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00116  189 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00167
cytochrome c oxidase subunit I; Provisional
 1-200 2.27e-119

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177222  Cd Length: 512  Bit Score: 347.82  E-value: 2.27e-119
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00167   29 VGTALSLLIRAELSQPGSLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00167  109 LLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGSINFITTIINMKPPGITQYQTPLFVWSI 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00167  189 LVTTILLLLSLPVLAAAITMLLTDRNLNTTFFDPAGGGDP 228
Cyt_c_Oxidase_I cd01663
Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the ...
 1-200 7.72e-116

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: 337.92  E-value: 7.72e-116
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:cd01663    20 VGTSLSLLIRLELSQPGSQLGNDQLYNVIVTAHALIMIFFMVMPALIGGFGNWLVPLMIGAPDMAFPRLNNLSFWLLPPS 99

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:cd01663   100 LLLLLLSALVEGGAGTGWTVYPPLSSILAHSGPSVDLAIFSLHLAGISSILGAINFITTIFNMRAPGMTLEKMPLFVWSV 179

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:cd01663   180 LITAFLLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 219
COX1 MTH00103
cytochrome c oxidase subunit I; Validated
 1-200 1.96e-112

cytochrome c oxidase subunit I; Validated


Pssm-ID: 177165  Cd Length: 513  Bit Score: 330.31  E-value: 1.96e-112
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00103   29 VGTALSLLIRAELGQPGTLLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00103  109 FLLLLASSMVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAMSQYQTPLFVWSV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00103  189 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 228
COX1 MTH00142
cytochrome c oxidase subunit I; Provisional
 1-200 6.49e-109

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214431  Cd Length: 511  Bit Score: 321.29  E-value: 6.49e-109
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00142   27 VGTGLSLLIRAELGQPGSLLGDDQLYNVIVTAHAFVMIFFMVMPVMIGGFGNWLVPLMLGAPDMAFPRMNNMSFWLLPPA 106

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00142  107 LLLLLSSAAVESGAGTGWTVYPPLSSNLAHSGGSVDLAIFSLHLAGVSSILGAINFITTVINMRAGGMKFERVPLFVWSV 186

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00142  187 KITAILLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 226
COX1 MTH00223
cytochrome c oxidase subunit I; Provisional
 1-200 3.53e-108

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177260  Cd Length: 512  Bit Score: 319.23  E-value: 3.53e-108
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00223   26 VGTSLSLLIRAELGQPGALLGDDQLYNVIVTAHAFVMIFFLVMPMMIGGFGNWLVPLMLGAPDMAFPRLNNMSFWLLPPS 105

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00223  106 LYLLLSSSAVESGVGTGWTVYPPLSSNLAHAGPSVDLAIFSLHLAGVSSILGAINFITTIINMRSPGMQLERLPLFVWSV 185

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00223  186 KVTAFLLLLSLPVLAGAITMLLTDRNFNTSFFDPAGGGDP 225
COX1 MTH00037
cytochrome c oxidase subunit I; Provisional
 1-200 6.29e-98

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177112  Cd Length: 517  Bit Score: 293.27  E-value: 6.29e-98
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00037   29 VGTAMSVIIRTELAQPGSLLQDDQIYNVIVTAHALVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLIPPS 108

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00037  109 FLLLLASAGVESGAGTGWTIYPPLSSNIAHAGGSVDLAIFSLHLAGASSILASINFITTIINMRTPGMTFDRLPLFVWSV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00037  189 FITAFLLLLSLPVLAGAITMLLTDRNINTTFFDPAGGGDP 228
COX1 MTH00007
cytochrome c oxidase subunit I; Validated
 1-200 1.77e-94

cytochrome c oxidase subunit I; Validated


Pssm-ID: 133649  Cd Length: 511  Bit Score: 284.10  E-value: 1.77e-94
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00007   26 LGTSMSLLIRIELGQPGAFLGSDQLYNTIVTAHAFLMIFFLVMPVFIGGFGNWLVPLMLGAPDMAFPRLNNMSFWLLPPA 105

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00007  106 LILLVSSAAVEKGVGTGWTVYPPLASNLAHAGPSVDLAIFSLHLAGVSSILGAINFITTVINMRWKGLRLERIPLFVWAV 185

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00007  186 VITVVLLLLSLPVLAGAITMLLTDRNLNTSFFDPAGGGDP 225
COX1 MTH00182
cytochrome c oxidase subunit I; Provisional
 1-200 2.28e-90

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214451  Cd Length: 525  Bit Score: 274.01  E-value: 2.28e-90
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00182   31 IGTAFSMLIRLELSAPGAMLGDDHLYNVIVTAHAFIMIFFLVMPVMIGGFGNWLVPLYIGAPDMAFPRLNNISFWLLPPA 110

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00182  111 LILLLGSAFVEQGAGTGWTVYPPLSSIQAHSGGAVDMAIFSLHLAGVSSILGAINFITTIFNMRAPGVTFNRLPLFVWSI 190

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00182  191 LITAFLLLLSLPVLAGAITMLLTDRNFNTTFFDPAGGGDP 230
COX1 MTH00184
cytochrome c oxidase subunit I; Provisional
 1-200 7.30e-90

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177235  Cd Length: 519  Bit Score: 272.47  E-value: 7.30e-90
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00184   31 IGTAFSMLIRLELSAPGSMLGDDHLYNVIVTAHAFVMIFFLVMPVMIGGFGNWFVPLYIGAPDMAFPRLNNISFWLLPPA 110

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00184  111 LTLLLGSAFVEQGAGTGWTVYPPLSSIQAHSGGSVDMAIFSLHLAGISSILGAMNFITTIFNMRAPGITMDRMPLFVWSI 190

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00184  191 LVTTFLLLLSLPVLAGAITMLLTDRNFNTTFFDPAGGGDP 230
COX1 MTH00079
cytochrome c oxidase subunit I; Provisional
 1-200 2.29e-83

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177148  Cd Length: 508  Bit Score: 255.76  E-value: 2.29e-83
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00079   30 VGTSLSLIIRLELSKPGLLLGNGQLYNSVITAHAILMIFFMVMPSMIGGFGNWMLPLMLGAPDMSFPRLNNLSFWLLPTS 109

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAgNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00079  110 LFLILDSCFVDMGPGTSWTVYPPLS-TLGHPGSSVDLAIFSLHCAGISSILGGINFMVTTKNLRSSSISLEHMSLFVWTV 188

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00079  189 FVTVFLLVLSLPVLAGAITMLLTDRNLNTSFFDPSTGGNP 228
COX1 MTH00026
cytochrome c oxidase subunit I; Provisional
 1-200 1.27e-81

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 164599  Cd Length: 534  Bit Score: 251.86  E-value: 1.27e-81
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00026   30 IGTAFSMLIRLELSSPGSMLGDDHLYNVIVTAHAFVMIFFLVMPTMIGGFGNWFVPLMIGAPDMAFPRLNNISFWLLPPA 109

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:MTH00026  110 LFLLLGSSLVEQGAGTGWTVYPPLASIQAHSGGSVDMAIFSLHLAGLSSILGAMNFITTVMNMRTPGMTMSRIPLFVWSV 189

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00026  190 FITAILLLLSLPVLAGAITMLLTDRNFNTTFFDPAGGGDP 229
Heme_Cu_Oxidase_I cd00919
Heme-copper oxidase subunit I. Heme-copper oxidases are transmembrane protein complexes in ...
 1-200 4.11e-72

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: 225.49  E-value: 4.11e-72
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPlMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:cd00919    18 LGGLLALLIRLELATPGSLFLDPQLYNQLVTAHGVIMIFFFVMPAIFGGFGNLLPP-LIGARDLAFPRLNNLSFWLFPPG 96

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:cd00919    97 LLLLLSSVLVGGGAGTGWTFYPPLSTLSYSSGVGVDLAILGLHLAGVSSILGAINFITTILNMRAPGMTLDKMPLFVWSV 176

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:cd00919   177 LVTAILLLLALPVLAAALVMLLLDRNFGTSFFDPAGGGDP 216
CyoB COG0843
Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];
1-200 1.67e-62

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


Pssm-ID: 440605  Cd Length: 535  Bit Score: 202.28  E-value: 1.67e-62
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:COG0843    32 IGGLLALLMRLQLAGPGLGLLSPETYNQLFTMHGTIMIFFFATP-FLAGFGNYLVPLQIGARDMAFPRLNALSFWLYLFG 110

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAV 160
Cdd:COG0843   111 GLLLLISLFVGGAADVGWTFYPPLSGLEASPGVGVDLWLLGLALFGVGSILGGVNFIVTILKMRAPGMTLMRMPLFTWAA 190

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:COG0843   191 LVTSILILLAFPVLAAALLLLLLDRSLGTHFFDPAGGGDP 230
COX1 MTH00048
cytochrome c oxidase subunit I; Provisional
 1-200 2.54e-55

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177123  Cd Length: 511  Bit Score: 182.96  E-value: 2.54e-55
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:MTH00048   30 VGLSLSLLIRLNFLDPYYNVISLDVYNFLITNHGIIMIFFFLMPVLIGGFGNYLLPLLLGLSDLNLPRLNALSAWLLVPS 109

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASsgVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISqYQTPLFVWAV 160
Cdd:MTH00048  110 IVFLLLS--MCLGAGVGWTFYPPLSSSLFSSSWGVDFLMFSLHLAGVSSLFGSINFICTIYSAFMTNVF-SRTSIILWSY 186

                         170       180       190       200
                  ....*....|....*....|....*....|....*....|
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:MTH00048  187 LFTSILLLLSLPVLAAAITMLLFDRNFGSAFFDPLGGGDP 226
Ubiquinol_Oxidase_I cd01662
Ubiquinol oxidase subunit I. Ubiquinol oxidase, the terminal oxidase in the respiratory ...
 2-200 6.03e-53

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: 176.62  E-value: 6.03e-53
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   2 GTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSF 81
Cdd:cd01662    25 GGVDALLMRTQLALPGNDFLSPEHYNQIFTMHGTIMIFLFAMPLVFG-LMNYLVPLQIGARDVAFPRLNALSFWLFLFGG 103

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  82 LLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAVL 161
Cdd:cd01662   104 LLLNASLLIGGFPDAGWFAYPPLSGLEYSPGVGVDYWILGLQFSGIGTLLGAINFIVTILKMRAPGMTLMRMPIFTWTTL 183

                         170       180       190
                  ....*....|....*....|....*....|....*....
gi 1852012659 162 ITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:cd01662   184 VTSILILFAFPVLTAALALLELDRYFGTHFFTNALGGNP 222
COX1 pfam00115
Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key ...
 1-195 4.66e-40

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: 141.17  E-value: 4.66e-40
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   1 VGTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPS 80
Cdd:pfam00115  16 VGGLLGLLIRLQLAFPGLNFLSPLTYNQLRTLHGNLMIFWFATP-FLFGFGNYLVPLMIGARDMAFPRLNALSFWLVVLG 94

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  81 FLLLLASSGveaGAGTGWTVYPPLAGnlahagasVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQyQTPLFVWAV 160
Cdd:pfam00115  95 AVLLLASFG---GATTGWTEYPPLVG--------VDLWYIGLLLAGVSSLLGAINFIVTILKRRAPGMTL-RMPLFVWAI 162

                         170       180       190
                  ....*....|....*....|....*....|....*
gi 1852012659 161 LITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPA 195
Cdd:pfam00115 163 LATAILILLAFPVLAAALLLLLLDRSLGAGGGDPL 197
PRK15017 PRK15017
cytochrome o ubiquinol oxidase subunit I; Provisional
 26-199 4.85e-35

cytochrome o ubiquinol oxidase subunit I; Provisional


Pssm-ID: 184978  Cd Length: 663  Bit Score: 130.06  E-value: 4.85e-35
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  26 YNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGWTVYPPLA 105
Cdd:PRK15017   99 YDQIFTAHGVIMIFFVAMPFVIG-LMNLVVPLQIGARDVAFPFLNNLSFWFTVVGVILVNVSLGVGEFAQTGWLAYPPLS 177

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659 106 GNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAVLITAVLLLLSLPVLAAGITMLLTDR 185
Cdd:PRK15017  178 GIEYSPGVGVDYWIWSLQLSGIGTTLTGINFFVTILKMRAPGMTMFKMPVFTWASLCANVLIIASFPILTVTVALLTLDR 257

                         170
                  ....*....|....
gi 1852012659 186 NLNTTFFDPAGGGD 199
Cdd:PRK15017  258 YLGTHFFTNDMGGN 271
QoxB TIGR02882
cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type ...
 2-200 6.47e-35

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: 129.59  E-value: 6.47e-35
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659   2 GTALSLLIRAELSQPGALLGDDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSF 81
Cdd:TIGR02882  68 GGIDALLMRAQLTVPDNKFLDAQHYNEIFTTHGVIMIIFMAMPFIIG-LMNIVVPLQIGARDVAFPVLNALSFWLFFAGA 146

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1852012659  82 LLLLASSGVEAGAGTGWTVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTIINMKPPSISQYQTPLFVWAVL 161
Cdd:TIGR02882 147 MLFNISFVIGGSPDAGWTNYAPLAGPEFSPGVGVNYYLIALQISGIGTLMTGINFFVTILKMRAPGMKLMQMPMFTWTTL 226

                         170       180       190
                  ....*....|....*....|....*....|....*....
gi 1852012659 162 ITAVLLLLSLPVLAAGITMLLTDRNLNTTFFDPAGGGDP 200
Cdd:TIGR02882 227 ITTLIIIFAFPVLTVALALMTTDRIFDTAFFTVAHGGMP 265
 
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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