Catalytic Mechanism of O2 Reduction by Cytochrome Oxidase
In the past it has been thought that the reduction of O2 to water catalysed by cytochrome oxidase would constitute an irreversible reaction step in the respiratiry chain. More recently it was shown that this is not the case, but that two consecutive one-electron steps of the catalytic cycle may be reversed at a high electrochemical proton gradient (1,2). This enabled identification of two spectrally distinct forms of the binuclear haem a3-copper centre, as probable intermediates of the catalytic process of O2 reduction. On the basis of such data a possible mechanism of catalysis has been proposed (1,2).
KeywordsPeroxide Sucrose Catalysis Titration Respiration
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