Cytochrome c oxidase is the terminal electron acceptor of mitochondria (and one of several possible acceptors in prokaryotes) in the electron transport chain of aerobic respiration. The enzyme couples the oxidation of reduced cytochrome c with the reduction of molecular oxygen to water. This process results in the pumping of four protons across the membrane which are used in the proton gradient powered synthesis of ATP. The oxidase contains two heme a cofactors and three copper atoms as well as other bound ions. [Energy metabolism, Electron transport]
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