Reaction: QH2 + 2 ferricytochrome c = Q + 2 ferrocytochrome c + 2 H+
Other name(s): coenzyme Q-cytochrome c reductase; dihydrocoenzyme Q-cytochrome c reductase; reduced ubiquinone-cytochrome c reductase, complex III (mitochondrial electron transport); ubiquinone-cytochrome c reductase; ubiquinol-cytochrome c oxidoreductase; reduced coenzyme Q-cytochrome c reductase; ubiquinone-cytochrome c oxidoreductase; reduced ubiquinone-cytochrome c oxidoreductase; mitochondrial electron transport complex III; ubiquinol-cytochrome c-2 oxidoreductase; ubiquinone-cytochrome b-c1 oxidoreductase; ubiquinol-cytochrome c2 reductase; ubiquinol-cytochrome c1 oxidoreductase; CoQH2-cytochrome c oxidoreductase; ubihydroquinol:cytochrome c oxidoreductase; coenzyme QH2-cytochrome c reductase; QH2:cytochrome c oxidoreductase
Systematic name: ubiquinol:ferricytochrome-c oxidoreductase
Comments: Contains cytochromes b-562, b-566 and c1, and a 2-iron ferredoxin. Depending on the organism and physiological conditions, either two or four protons are extruded from the cytoplasmic to the non-cytoplasmic compartment (cf. EC 1.6.99.3 NADH dehydrogenase).
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9027-03-6
References:
1. Marres, C.A.M. and Slater, E.C. Polypeptide composition of purified QH2:cytochrome c oxidoreductase from beef-heart mitochondria. Biochim. Biophys. Acta 462 (1977) 531-548. [PMID: 597492]
2. Rieske, J.S. Composition, structure, and function of complex III of the respiratory chain. Biochim. Biophys. Acta 456 (1976) 195-247. [PMID: 788795]
3. Wikström, M., Krab, K. and Saraste, M. Proton-translocating cytochrome complexes. Annu. Rev. Biochem. 50 (1981) 623-655. [PMID: 6267990]