The oxidation-reduction potential of cozymase (diphosphopyridine nucleotide) was calculated from the free energies of formation of aqueous d-alanine and d-glutamic acid based on thermal data, and the equilibria measured by Wurmser and Filitti-Wurmser’ for pyruvate + 2H+ + 2(e) + alanine + HzO, by Cohen2 for a-ketoglutarate + alanine s d-glutamate and pyruvate, and by von Euler et aLa for the re...