A theoretical mechanism (proposed by Mitchell) to explain energy transduction in the mitochondrion. As a general mechanism it is the coupling of one enzyme-catalysed reaction to another using the transmembrane flow of an intermediate species, eg. cytochrome oxidase pumps protons across the mitochondrial inner membrane and ATP synthesis is ‘driven’ by re-entry of protons through the ATP-synthesizing protein complex. The alternative model is production of a chemical intermediate species, but no compound capable of coupling these reactions has ever been identified.
Dictionary of molecular biology. 2004.