Q95840 · COX3_PYRGI
- ProteinCytochrome c oxidase subunit 3
- GeneCOX3
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids269 (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] + 8 H+(in) + O2 = 4 Fe(III)-[cytochrome c] + 4 H+(out) + 2 H2OThis reaction proceeds in the forward direction.
4 RHEA-COMP:10350 + 8 H+ (in)CHEBI:15378+ CHEBI:15379 = 4 RHEA-COMP:14399 + 4 H+ (out)CHEBI:15378+ 2 CHEBI:15377
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | mitochondrial inner membrane | |
Molecular Function | cytochrome-c oxidase activity | |
Biological Process | aerobic electron transport chain |
Keywords
- Molecular function
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameCytochrome c oxidase subunit 3
- EC number
- Alternative names
Gene names
Encoded on
- Mitochondrion
Organism names
- Taxonomic lineageEukaryota > Fungi > Dikarya > Ascomycota > Pezizomycotina > Sordariomycetes > Sordariomycetidae > Magnaporthales > Pyriculariaceae > Pyricularia
Accessions
- Primary accessionQ95840
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Mitochondrion inner membrane ; Multi-pass membrane protein
Features
Showing features for transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Transmembrane | 13-33 | Helical | ||||
Sequence: PFHLVSPSLWPLYTSISLLVL | ||||||
Transmembrane | 46-66 | Helical | ||||
Sequence: NGHYSVYLGLILVISSMSFWF | ||||||
Transmembrane | 90-110 | Helical | ||||
Sequence: GVILFIVSEALFFMAIFWAFF | ||||||
Transmembrane | 138-160 | Helical | ||||
Sequence: PLLNTVILLSSGATVTYAHHSII | ||||||
Transmembrane | 167-187 | Helical | ||||
Sequence: ALYGSVATVLLAIVFTGFQGV | ||||||
Transmembrane | 207-227 | Helical | ||||
Sequence: FGTGFHGLHVIIGTIFLLVAL | ||||||
Transmembrane | 245-265 | Helical | ||||
Sequence: AGILYWHFVDVVWLFLYISIY |
Keywords
- Cellular component
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000183805 | 1-269 | Cytochrome c oxidase subunit 3 | |||
Sequence: MNNLVRSNFQDHPFHLVSPSLWPLYTSISLLVLTSNAALAMHNFANGHYSVYLGLILVISSMSFWFRDVITEGSFLGDHTLAVQKGLNLGVILFIVSEALFFMAIFWAFFHSALTPTVELGGQWPPIGIEPINPFELPLLNTVILLSSGATVTYAHHSIIGRNREGALYGSVATVLLAIVFTGFQGVEYSVSSFTISDGAFGTCFYFGTGFHGLHVIIGTIFLLVALWRIFAYHLTDNHHLGFEAGILYWHFVDVVWLFLYISIYYWGS |
Interaction
Subunit
Component of the cytochrome c oxidase (complex IV, CIV), a multisubunit enzyme composed of a catalytic core of 3 subunits and several supernumerary subunits. The complex exists as a monomer or a dimer and forms supercomplexes (SCs) in the inner mitochondrial membrane with ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII).
Structure
Sequence
- Sequence statusComplete
- Length269
- Mass (Da)29,981
- Last updated1997-02-01 v1
- ChecksumAC71B68747D03FCC
Keywords
- Technical term