Cytochrome c oxidase subunit 5A, mitochondrial (Cytochrome c oxidase polypeptide Va)
1_MLGAA 6_ LRRCA 11_ VAATT 16_ RADPR 21_ GLLHS 26_ ARTPG 31_ PAVAI 36_ QSVRC 41_ YSHGS 46_ QETDE 51_ EFDAR 56_ WVTYF 61_ NKPDI 66_ DAWEL 71_ RKGIN 76_ TLVTY 81_ DMVPE 86_ PKIID 91_ AALRA 96_ CRRLN 101_ DFAST 106_ VRILE 111_ VVKDK 116_ AGPHK 121_ EIYPY 126_ VIQEL 131_ RPTLN 136_ ELGIS 141_TPEEL
1: 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