Q9B2U6 · Q9B2U6_HUMAN
- ProteinCytochrome c oxidase subunit 3
- GeneCOX3
- StatusUniProtKB unreviewed (TrEMBL)
- Organism
- Amino acids260 (go to sequence)
- Protein existenceInferred from homology
- Annotation score2/5
Function
function
Component of the cytochrome c oxidase, the last enzyme in the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient over the inner membrane that drives transmembrane transport and the ATP synthase. Cytochrome c oxidase is the component of the respiratory chain that catalyzes the reduction of oxygen to water. Electrons originating from reduced cytochrome c in the intermembrane space (IMS) are transferred via the dinuclear copper A center (CU(A)) of subunit 2 and heme A of subunit 1 to the active site in subunit 1, a binuclear center (BNC) formed by heme A3 and copper B (CU(B)). The BNC reduces molecular oxygen to 2 water molecules using 4 electrons from cytochrome c in the IMS and 4 protons from the mitochondrial matrix.
Catalytic activity
- 4 Fe(II)-[cytochrome c] + O2 + 8 H+(in) = 4 Fe(III)-[cytochrome c] + 2 H2O + 4 H+(out)This reaction proceeds in the forward direction.
4 RHEA-COMP:10350 + CHEBI:15379 + 8 H+ (in)CHEBI:15378= 4 RHEA-COMP:14399 + 2 CHEBI:15377 + 4 H+ (out)CHEBI:15378
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | membrane | |
Cellular Component | mitochondrion | |
Molecular Function | cytochrome-c oxidase activity | |
Biological Process | aerobic electron transport chain |
Keywords
- Molecular function
Names & Taxonomy
Protein names
- Recommended nameCytochrome c oxidase subunit 3
Gene names
Encoded on
- Mitochondrion
Organism names
- Organism
- Strains
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Homo
Accessions
- Primary accessionQ9B2U6
Subcellular Location
UniProt Annotation
GO Annotation
Membrane ; Multi-pass membrane protein
Features
Showing features for transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Transmembrane | 16-35 | Helical | ||||
Sequence: WPLTGALSALLMTSGLAMWF | ||||||
Transmembrane | 41-58 | Helical | ||||
Sequence: TLLMLGLLTNTLTMYQWW | ||||||
Transmembrane | 79-102 | Helical | ||||
Sequence: LRYGMILFITSEVFFFAGFFWAFY | ||||||
Transmembrane | 159-177 | Helical | ||||
Sequence: MIQALLITILLGLYFTLLQ | ||||||
Transmembrane | 197-220 | Helical | ||||
Sequence: FFVATGFHGLHVIIGSTFLTICFI | ||||||
Transmembrane | 240-259 | Helical | ||||
Sequence: WYWHFVDVVWLFLYVSIYWW |
Keywords
- Cellular component
PTM/Processing
Proteomic databases
Structure
Family & Domains
Features
Showing features for domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 4-260 | Heme-copper oxidase subunit III family profile | ||||
Sequence: QSHAYHMVKPSPWPLTGALSALLMTSGLAMWFHFHSMTLLMLGLLTNTLTMYQWWRDVTRESTYQGHHTPPVQKGLRYGMILFITSEVFFFAGFFWAFYHSSLAPTPQLGGHWPPTGITPLNPLEVPLLNTSVLLASGVSITWAHHSLMESNRNQMIQALLITILLGLYFTLLQASEYFESPFTISDGIYGSTFFVATGFHGLHVIIGSTFLTICFIRQLMFHFTSKHHFGFEAAAWYWHFVDVVWLFLYVSIYWWG |
Sequence similarities
Belongs to the cytochrome c oxidase subunit 3 family.
Keywords
- Domain
Family and domain databases
Sequence
- Sequence statusComplete
- Length260
- Mass (Da)29,837
- Last updated2001-06-01 v1
- ChecksumD1CCC4E529F63C2A
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AF347010 EMBL· GenBank· DDBJ | AAK17824.2 EMBL· GenBank· DDBJ | Genomic DNA | ||
AF381997 EMBL· GenBank· DDBJ | AAL54598.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EF657295 EMBL· GenBank· DDBJ | ABR93809.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660538 EMBL· GenBank· DDBJ | ACC86307.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660539 EMBL· GenBank· DDBJ | ACC86320.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660540 EMBL· GenBank· DDBJ | ACC86333.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660541 EMBL· GenBank· DDBJ | ACC86346.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660542 EMBL· GenBank· DDBJ | ACC86359.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660543 EMBL· GenBank· DDBJ | ACC86372.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660544 EMBL· GenBank· DDBJ | ACC86385.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660545 EMBL· GenBank· DDBJ | ACC86398.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660546 EMBL· GenBank· DDBJ | ACC86411.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660547 EMBL· GenBank· DDBJ | ACC86424.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660553 EMBL· GenBank· DDBJ | ACC86502.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660554 EMBL· GenBank· DDBJ | ACC86515.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660555 EMBL· GenBank· DDBJ | ACC86528.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660556 EMBL· GenBank· DDBJ | ACC86541.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660557 EMBL· GenBank· DDBJ | ACC86554.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660558 EMBL· GenBank· DDBJ | ACC86567.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660559 EMBL· GenBank· DDBJ | ACC86580.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660560 EMBL· GenBank· DDBJ | ACC86593.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660561 EMBL· GenBank· DDBJ | ACC86606.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660562 EMBL· GenBank· DDBJ | ACC86619.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660563 EMBL· GenBank· DDBJ | ACC86632.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660564 EMBL· GenBank· DDBJ | ACC86645.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660565 EMBL· GenBank· DDBJ | ACC86658.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660566 EMBL· GenBank· DDBJ | ACC86671.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660567 EMBL· GenBank· DDBJ | ACC86684.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660568 EMBL· GenBank· DDBJ | ACC86697.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660569 EMBL· GenBank· DDBJ | ACC86710.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660570 EMBL· GenBank· DDBJ | ACC86723.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660571 EMBL· GenBank· DDBJ | ACC86736.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660572 EMBL· GenBank· DDBJ | ACC86749.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
EU660573 EMBL· GenBank· DDBJ | ACC86762.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
GQ337682 EMBL· GenBank· DDBJ | ACU11438.1 EMBL· GenBank· DDBJ | Genomic DNA |