UniProt functional annotation for P00420



	UniProt functional annotation for P00420

UniProt code: P00420.

Organism: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).

Taxonomy: Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; Saccharomycetes; Saccharomycetales; Saccharomycetaceae; Saccharomyces.

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 COX2 and heme A of COX1 to the active site in COX1, 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 (Probable). COX3 is a catalytic core subunit (PubMed:30598554). {ECO:0000269|PubMed:30598554, ECO:0000305|PubMed:30598554}.

Catalytic activity: Reaction=4 [Fe(II)cytochrome c] + 4 H(+) + O2 = 4 [Fe(III)cytochrome c] + 2 H2O; Xref=Rhea:RHEA:11436, Rhea:RHEA-COMP:10350, Rhea:RHEA- COMP:14399, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:29033, ChEBI:CHEBI:29034; EC=7.1.1.9; Evidence={ECO:0000269|PubMed:30598554}; PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:11437; Evidence={ECO:0000269|PubMed:30598554};

Subunit: Component of the cytochrome c oxidase (complex IV, CIV), a multisubunit enzyme composed of 12 subunits. The complex is composed of a catalytic core of 3 subunits COX1, COX2 and COX3, encoded in the mitochondrial DNA, and 9 supernumerary subunits COX4, COX5A (or COX5B), COX6, COX7, COX8, COX9, COX12, COX13 and COX26, which are encoded in the nuclear genome (PubMed:7851399, PubMed:30598556, PubMed:30598554). The complex exists as a monomer or a dimer and forms supercomplexes (SCs) in the inner mitochondrial membrane with a dimer of ubiquinol- cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII), resulting in 2 different assemblies (supercomplexes III(2)IV and III(2)IV(2)) (PubMed:10775262, PubMed:10764779, PubMed:30598556, PubMed:30598554). {ECO:0000269|PubMed:10764779, ECO:0000269|PubMed:10775262, ECO:0000269|PubMed:30598554, ECO:0000269|PubMed:30598556, ECO:0000269|PubMed:7851399}.

Subcellular location: Mitochondrion inner membrane {ECO:0000269|PubMed:30598554}; Multi-pass membrane protein {ECO:0000269|PubMed:30598554}.

Ptm: The N-terminus is blocked. {ECO:0000269|PubMed:7851399}.

Similarity: Belongs to the cytochrome c oxidase subunit 3 family. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast).
Taxonomy:		Eukaryota; Fungi; Dikarya; Ascomycota; Saccharomycotina; Saccharomycetes; Saccharomycetales; Saccharomycetaceae; Saccharomyces.



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 COX2 and heme A of COX1 to the active site in COX1, 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 (Probable). COX3 is a catalytic core subunit (PubMed:30598554). {ECO:0000269\|PubMed:30598554, ECO:0000305\|PubMed:30598554}.


Catalytic activity:		Reaction=4 [Fe(II)cytochrome c] + 4 H(+) + O2 = 4 [Fe(III)cytochrome c] + 2 H2O; Xref=Rhea:RHEA:11436, Rhea:RHEA-COMP:10350, Rhea:RHEA- COMP:14399, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:29033, ChEBI:CHEBI:29034; EC=7.1.1.9; Evidence={ECO:0000269\|PubMed:30598554}; PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:11437; Evidence={ECO:0000269\|PubMed:30598554};
Subunit:		Component of the cytochrome c oxidase (complex IV, CIV), a multisubunit enzyme composed of 12 subunits. The complex is composed of a catalytic core of 3 subunits COX1, COX2 and COX3, encoded in the mitochondrial DNA, and 9 supernumerary subunits COX4, COX5A (or COX5B), COX6, COX7, COX8, COX9, COX12, COX13 and COX26, which are encoded in the nuclear genome (PubMed:7851399, PubMed:30598556, PubMed:30598554). The complex exists as a monomer or a dimer and forms supercomplexes (SCs) in the inner mitochondrial membrane with a dimer of ubiquinol- cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII), resulting in 2 different assemblies (supercomplexes III(2)IV and III(2)IV(2)) (PubMed:10775262, PubMed:10764779, PubMed:30598556, PubMed:30598554). {ECO:0000269\|PubMed:10764779, ECO:0000269\|PubMed:10775262, ECO:0000269\|PubMed:30598554, ECO:0000269\|PubMed:30598556, ECO:0000269\|PubMed:7851399}.
Subcellular location:		Mitochondrion inner membrane {ECO:0000269\|PubMed:30598554}; Multi-pass membrane protein {ECO:0000269\|PubMed:30598554}.
Ptm:		The N-terminus is blocked. {ECO:0000269\|PubMed:7851399}.
Similarity:		Belongs to the cytochrome c oxidase subunit 3 family. {ECO:0000305}.