Mechanism of NADH transfer among dehydrogenases.
Steady-state and transient-state kinetic experiments have been performed to test the proposal that there is a direct (channelled) transfer of NADH from one dehydrogenase to another if the two enzymes exhibit distinct chiral coenzyme specificity (A-side vs. B-side). The results lend no support to this proposal, but are fully consistent with a free-diffusion mechanism of NADH transfer irrespective of the chiral specificity of the enzymes.