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Conserved domains on  [gi|2559708820|dbj|BDX23760|]
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cytochrome c oxidase subunit 1, partial (mitochondrion) [Eviota abax]

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 ...
 1-161 3.64e-100

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: 297.22  E-value: 3.64e-100
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00183   47 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 126

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLITAVLLLLSLPVLAAGI 160
Cdd:MTH00183  127 TVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAISQYQTPLFVWAVLITAVLLLLSLPVLAAGI 206


                  .
gi 2559708820 161 T 161
Cdd:MTH00183  207 T 207
 
Name Accession Description Interval E-value
COX1 MTH00183
cytochrome c oxidase subunit I; Provisional
 1-161 3.64e-100

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177234  Cd Length: 516  Bit Score: 297.22  E-value: 3.64e-100
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00183   47 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 126

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLITAVLLLLSLPVLAAGI 160
Cdd:MTH00183  127 TVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAISQYQTPLFVWAVLITAVLLLLSLPVLAAGI 206


                  .
gi 2559708820 161 T 161
Cdd:MTH00183  207 T 207
Cyt_c_Oxidase_I cd01663
Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the ...
 1-145 2.24e-85

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: 258.57  E-value: 2.24e-85
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:cd01663    38 QLGNDQLYNVIVTAHALIMIFFMVMPALIGGFGNWLVPLMIGAPDMAFPRLNNLSFWLLPPSLLLLLLSALVEGGAGTGW 117

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:cd01663   118 TVYPPLSSILAHSGPSVDLAIFSLHLAGISSILGAINFITTIFNMRAPGMTLEKMPLFVWSVLIT 182
CyoB COG0843
Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];
8-145 5.14e-47

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


Pssm-ID: 440605  Cd Length: 535  Bit Score: 159.91  E-value: 5.14e-47
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   8 YNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGWTVYPPLA 87
Cdd:COG0843    57 YNQLFTMHGTIMIFFFATP-FLAGFGNYLVPLQIGARDMAFPRLNALSFWLYLFGGLLLLISLFVGGAADVGWTFYPPLS 135

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 2559708820  88 GNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:COG0843   136 GLEASPGVGVDLWLLGLALFGVGSILGGVNFIVTILKMRAPGMTLMRMPLFTWAALVT 193
COX1 pfam00115
Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key ...
 1-145 1.20e-28

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: 109.20  E-value: 1.20e-28
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGveaGAGTGW 80
Cdd:pfam00115  34 NFLSPLTYNQLRTLHGNLMIFWFATP-FLFGFGNYLVPLMIGARDMAFPRLNALSFWLVVLGAVLLLASFG---GATTGW 109

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGnlahagasVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQyQTPLFVWAVLIT 145
Cdd:pfam00115 110 TEYPPLVG--------VDLWYIGLLLAGVSSLLGAINFIVTILKRRAPGMTL-RMPLFVWAILAT 165
QoxB TIGR02882
cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type ...
 4-145 8.15e-28

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: 108.02  E-value: 8.15e-28
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   4 DDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGWTVY 83
Cdd:TIGR02882  88 DAQHYNEIFTTHGVIMIIFMAMPFIIG-LMNIVVPLQIGARDVAFPVLNALSFWLFFAGAMLFNISFVIGGSPDAGWTNY 166

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2559708820  84 PPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:TIGR02882 167 APLAGPEFSPGVGVNYYLIALQISGIGTLMTGINFFVTILKMRAPGMKLMQMPMFTWTTLIT 228
 
Name Accession Description Interval E-value
COX1 MTH00183
cytochrome c oxidase subunit I; Provisional
 1-161 3.64e-100

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177234  Cd Length: 516  Bit Score: 297.22  E-value: 3.64e-100
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00183   47 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 126

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLITAVLLLLSLPVLAAGI 160
Cdd:MTH00183  127 TVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAISQYQTPLFVWAVLITAVLLLLSLPVLAAGI 206


                  .
gi 2559708820 161 T 161
Cdd:MTH00183  207 T 207
COX1 MTH00103
cytochrome c oxidase subunit I; Validated
 1-161 1.07e-99

cytochrome c oxidase subunit I; Validated


Pssm-ID: 177165  Cd Length: 513  Bit Score: 296.02  E-value: 1.07e-99
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00103   47 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSMVEAGAGTGW 126

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLITAVLLLLSLPVLAAGI 160
Cdd:MTH00103  127 TVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTIINMKPPAMSQYQTPLFVWSVLITAVLLLLSLPVLAAGI 206


                  .
gi 2559708820 161 T 161
Cdd:MTH00103  207 T 207
COX1 MTH00077
cytochrome c oxidase subunit I; Provisional
 1-161 2.01e-99

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214419  Cd Length: 514  Bit Score: 295.31  E-value: 2.01e-99
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00077   47 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 126

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLITAVLLLLSLPVLAAGI 160
Cdd:MTH00077  127 TVYPPLAGNLAHAGASVDLTIFSLHLAGVSSILGAINFITTSINMKPPSMSQYQTPLFVWSVLITAVLLLLSLPVLAAGI 206


                  .
gi 2559708820 161 T 161
Cdd:MTH00077  207 T 207
COX1 MTH00153
cytochrome c oxidase subunit I; Provisional
 1-145 1.02e-91

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177210  Cd Length: 511  Bit Score: 275.21  E-value: 1.02e-91
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00153   45 LIGDDQIYNVIVTAHAFIMIFFMVMPIMIGGFGNWLVPLMLGAPDMAFPRMNNMSFWLLPPSLTLLLSSSMVESGAGTGW 124

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00153  125 TVYPPLSSNIAHSGASVDLAIFSLHLAGISSILGAINFITTIINMRSKGMTLDRMPLFVWSVLIT 189
COX1 MTH00116
cytochrome c oxidase subunit I; Provisional
 1-161 3.53e-90

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177177  Cd Length: 515  Bit Score: 271.58  E-value: 3.53e-90
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00116   47 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSTVEAGAGTGW 126

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLITAVLLLLSLPVLAAGI 160
Cdd:MTH00116  127 TVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGAINFITTCINMKPPAMSQYQTPLFVWSVLITAVLLLLSLPVLAAGI 206


                  .
gi 2559708820 161 T 161
Cdd:MTH00116  207 T 207
COX1 MTH00167
cytochrome c oxidase subunit I; Provisional
 1-145 3.00e-87

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177222  Cd Length: 512  Bit Score: 263.85  E-value: 3.00e-87
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00167   47 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLVPLMIGAPDMAFPRMNNMSFWLLPPSLLLLLASSGVEAGAGTGW 126

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00167  127 TVYPPLAGNLAHAGASVDLAIFSLHLAGVSSILGSINFITTIINMKPPGITQYQTPLFVWSILVT 191
Cyt_c_Oxidase_I cd01663
Cytochrome C oxidase subunit I. Cytochrome c oxidase (CcO), the terminal oxidase in the ...
 1-145 2.24e-85

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: 258.57  E-value: 2.24e-85
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:cd01663    38 QLGNDQLYNVIVTAHALIMIFFMVMPALIGGFGNWLVPLMIGAPDMAFPRLNNLSFWLLPPSLLLLLLSALVEGGAGTGW 117

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:cd01663   118 TVYPPLSSILAHSGPSVDLAIFSLHLAGISSILGAINFITTIFNMRAPGMTLEKMPLFVWSVLIT 182
COX1 MTH00142
cytochrome c oxidase subunit I; Provisional
 1-145 8.96e-79

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214431  Cd Length: 511  Bit Score: 242.32  E-value: 8.96e-79
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00142   45 LLGDDQLYNVIVTAHAFVMIFFMVMPVMIGGFGNWLVPLMLGAPDMAFPRMNNMSFWLLPPALLLLLSSAAVESGAGTGW 124

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00142  125 TVYPPLSSNLAHSGGSVDLAIFSLHLAGVSSILGAINFITTVINMRAGGMKFERVPLFVWSVKIT 189
COX1 MTH00223
cytochrome c oxidase subunit I; Provisional
 1-145 3.43e-78

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177260  Cd Length: 512  Bit Score: 240.65  E-value: 3.43e-78
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00223   44 LLGDDQLYNVIVTAHAFVMIFFLVMPMMIGGFGNWLVPLMLGAPDMAFPRLNNMSFWLLPPSLYLLLSSSAVESGVGTGW 123

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00223  124 TVYPPLSSNLAHAGPSVDLAIFSLHLAGVSSILGAINFITTIINMRSPGMQLERLPLFVWSVKVT 188
COX1 MTH00037
cytochrome c oxidase subunit I; Provisional
 1-145 7.73e-71

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177112  Cd Length: 517  Bit Score: 222.01  E-value: 7.73e-71
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00037   47 LLQDDQIYNVIVTAHALVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLIPPSFLLLLASAGVESGAGTGW 126

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00037  127 TIYPPLSSNIAHAGGSVDLAIFSLHLAGASSILASINFITTIINMRTPGMTFDRLPLFVWSVFIT 191
COX1 MTH00007
cytochrome c oxidase subunit I; Validated
 1-145 5.36e-67

cytochrome c oxidase subunit I; Validated


Pssm-ID: 133649  Cd Length: 511  Bit Score: 211.68  E-value: 5.36e-67
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00007   44 FLGSDQLYNTIVTAHAFLMIFFLVMPVFIGGFGNWLVPLMLGAPDMAFPRLNNMSFWLLPPALILLVSSAAVEKGVGTGW 123

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00007  124 TVYPPLASNLAHAGPSVDLAIFSLHLAGVSSILGAINFITTVINMRWKGLRLERIPLFVWAVVIT 188
COX1 MTH00182
cytochrome c oxidase subunit I; Provisional
 1-145 3.64e-64

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 214451  Cd Length: 525  Bit Score: 204.67  E-value: 3.64e-64
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00182   49 MLGDDHLYNVIVTAHAFIMIFFLVMPVMIGGFGNWLVPLYIGAPDMAFPRLNNISFWLLPPALILLLGSAFVEQGAGTGW 128

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00182  129 TVYPPLSSIQAHSGGAVDMAIFSLHLAGVSSILGAINFITTIFNMRAPGVTFNRLPLFVWSILIT 193
COX1 MTH00184
cytochrome c oxidase subunit I; Provisional
 1-161 7.91e-64

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177235  Cd Length: 519  Bit Score: 203.90  E-value: 7.91e-64
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00184   49 MLGDDHLYNVIVTAHAFVMIFFLVMPVMIGGFGNWFVPLYIGAPDMAFPRLNNISFWLLPPALTLLLGSAFVEQGAGTGW 128

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLITAVLLLLSLPVLAAGI 160
Cdd:MTH00184  129 TVYPPLSSIQAHSGGSVDMAIFSLHLAGISSILGAMNFITTIFNMRAPGITMDRMPLFVWSILVTTFLLLLSLPVLAGAI 208


                  .
gi 2559708820 161 T 161
Cdd:MTH00184  209 T 209
COX1 MTH00026
cytochrome c oxidase subunit I; Provisional
 1-145 1.49e-58

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 164599  Cd Length: 534  Bit Score: 190.22  E-value: 1.49e-58
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00026   48 MLGDDHLYNVIVTAHAFVMIFFLVMPTMIGGFGNWFVPLMIGAPDMAFPRLNNISFWLLPPALFLLLGSSLVEQGAGTGW 127

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00026  128 TVYPPLASIQAHSGGSVDMAIFSLHLAGLSSILGAMNFITTVMNMRTPGMTMSRIPLFVWSVFIT 192
COX1 MTH00079
cytochrome c oxidase subunit I; Provisional
 1-145 2.02e-58

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177148  Cd Length: 508  Bit Score: 189.51  E-value: 2.02e-58
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:MTH00079   48 LLGNGQLYNSVITAHAILMIFFMVMPSMIGGFGNWMLPLMLGAPDMSFPRLNNLSFWLLPTSLFLILDSCFVDMGPGTSW 127

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAgNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:MTH00079  128 TVYPPLS-TLGHPGSSVDLAIFSLHCAGISSILGGINFMVTTKNLRSSSISLEHMSLFVWTVFVT 191
Heme_Cu_Oxidase_I cd00919
Heme-copper oxidase subunit I. Heme-copper oxidases are transmembrane protein complexes in ...
 1-145 3.83e-50

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: 166.55  E-value: 3.83e-50
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPlMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGW 80
Cdd:cd00919    36 LFLDPQLYNQLVTAHGVIMIFFFVMPAIFGGFGNLLPP-LIGARDLAFPRLNNLSFWLFPPGLLLLLSSVLVGGGAGTGW 114

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:cd00919   115 TFYPPLSTLSYSSGVGVDLAILGLHLAGVSSILGAINFITTILNMRAPGMTLDKMPLFVWSVLVT 179
CyoB COG0843
Heme/copper-type cytochrome/quinol oxidase, subunit 1 [Energy production and conversion];
8-145 5.14e-47

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


Pssm-ID: 440605  Cd Length: 535  Bit Score: 159.91  E-value: 5.14e-47
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   8 YNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGWTVYPPLA 87
Cdd:COG0843    57 YNQLFTMHGTIMIFFFATP-FLAGFGNYLVPLQIGARDMAFPRLNALSFWLYLFGGLLLLISLFVGGAADVGWTFYPPLS 135

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 2559708820  88 GNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:COG0843   136 GLEASPGVGVDLWLLGLALFGVGSILGGVNFIVTILKMRAPGMTLMRMPLFTWAALVT 193
Ubiquinol_Oxidase_I cd01662
Ubiquinol oxidase subunit I. Ubiquinol oxidase, the terminal oxidase in the respiratory ...
 8-145 3.89e-41

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: 143.49  E-value: 3.89e-41
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   8 YNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGWTVYPPLA 87
Cdd:cd01662    49 YNQIFTMHGTIMIFLFAMPLVFG-LMNYLVPLQIGARDVAFPRLNALSFWLFLFGGLLLNASLLIGGFPDAGWFAYPPLS 127

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 2559708820  88 GNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:cd01662   128 GLEYSPGVGVDYWILGLQFSGIGTLLGAINFIVTILKMRAPGMTLMRMPIFTWTTLVT 185
COX1 MTH00048
cytochrome c oxidase subunit I; Provisional
 7-161 3.08e-36

cytochrome c oxidase subunit I; Provisional


Pssm-ID: 177123  Cd Length: 511  Bit Score: 130.57  E-value: 3.08e-36
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   7 IYNVIVTAHAFVMIFFMVMPIMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASsgVEAGAGTGWTVYPPL 86
Cdd:MTH00048   54 VYNFLITNHGIIMIFFFLMPVLIGGFGNYLLPLLLGLSDLNLPRLNALSAWLLVPSIVFLLLS--MCLGAGVGWTFYPPL 131

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  87 AGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSqYQTPLFVWAVLITAVLLLLSLPVLAAGIT 161
Cdd:MTH00048  132 SSSLFSSSWGVDFLMFSLHLAGVSSLFGSINFICTIYSAFMTNVF-SRTSIILWSYLFTSILLLLSLPVLAAAIT 205
PRK15017 PRK15017
cytochrome o ubiquinol oxidase subunit I; Provisional
 8-145 8.49e-32

cytochrome o ubiquinol oxidase subunit I; Provisional


Pssm-ID: 184978  Cd Length: 663  Bit Score: 119.27  E-value: 8.49e-32
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   8 YNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGWTVYPPLA 87
Cdd:PRK15017   99 YDQIFTAHGVIMIFFVAMPFVIG-LMNLVVPLQIGARDVAFPFLNNLSFWFTVVGVILVNVSLGVGEFAQTGWLAYPPLS 177

                          90       100       110       120       130
                  ....*....|....*....|....*....|....*....|....*....|....*...
gi 2559708820  88 GNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:PRK15017  178 GIEYSPGVGVDYWIWSLQLSGIGTTLTGINFFVTILKMRAPGMTMFKMPVFTWASLCA 235
COX1 pfam00115
Cytochrome C and Quinol oxidase polypeptide I; Cytochrome c oxidase (E.C:7.1.1.9) is a key ...
 1-145 1.20e-28

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: 109.20  E-value: 1.20e-28
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   1 LLGDDQIYNVIVTAHAFVMIFFMVMPiMIGGFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGveaGAGTGW 80
Cdd:pfam00115  34 NFLSPLTYNQLRTLHGNLMIFWFATP-FLFGFGNYLVPLMIGARDMAFPRLNALSFWLVVLGAVLLLASFG---GATTGW 109

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 2559708820  81 TVYPPLAGnlahagasVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQyQTPLFVWAVLIT 145
Cdd:pfam00115 110 TEYPPLVG--------VDLWYIGLLLAGVSSLLGAINFIVTILKRRAPGMTL-RMPLFVWAILAT 165
QoxB TIGR02882
cytochrome aa3 quinol oxidase, subunit I; This family (QoxB) encodes subunit I of the aa3-type ...
 4-145 8.15e-28

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: 108.02  E-value: 8.15e-28
                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 2559708820   4 DDQIYNVIVTAHAFVMIFFMVMPIMIGgFGNWLIPLMIGAPDMAFPRMNNMSFWLLPPSFLLLLASSGVEAGAGTGWTVY 83
Cdd:TIGR02882  88 DAQHYNEIFTTHGVIMIIFMAMPFIIG-LMNIVVPLQIGARDVAFPVLNALSFWLFFAGAMLFNISFVIGGSPDAGWTNY 166

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|..
gi 2559708820  84 PPLAGNLAHAGASVDLTIFSLHLAGISSILGAINFITTILNMKPPAMSQYQTPLFVWAVLIT 145
Cdd:TIGR02882 167 APLAGPEFSPGVGVNYYLIALQISGIGTLMTGINFFVTILKMRAPGMKLMQMPMFTWTTLIT 228
 
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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