Cytochrome oxidase as a redox-linked proton pump.

Some general principles for redox-linked proton pumps are described and applied to cytochrome oxidase. A reaction scheme obeying these principles is described. The scheme includes electron transfer between the redox centers of the oxidase, the mechanism of dioxygen reduction, protonation and deprotonation steps for both scalar and vectorial protons, as well as input-output transitions for electrons and protons. It is consistent with a large amount of kinetic information.