MT-CO1
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.
Pathway
Energy metabolism; oxidative phosphorylation.
Post-translational modifications
His-240 and Tyr-244 are involved in the formation of a copper-coordinated covalent cross-link at the active site of the catalytic subunit I.
Sequence Similarities
Belongs to the heme-copper respiratory oxidase family.
Cellular localization
- Mitochondrion inner membrane
- Multi-pass membrane protein
Alternative names
COI, COXI, MTCO1, MT-CO1, Cytochrome c oxidase subunit 1, Cytochrome c oxidase polypeptide I