Intramolecular hydride transfer of a combined coenzyme-substrate analog by D- and L-lactate dehydrogenases

The synthesis of 3-[(3-carboxy-3-oxopropyl)aminocarbonyl]pyridine adenine dinucleotide, a new combined analog of NADH and pyruvate with pyruvate covalently attached to the amide nitrogen atom of the dihydronicotinamide ring via an additional methylene group, is described. In the presence of D-lactate dehydrogenase from Limulus polyphemus, from Lactobacillus leichmannii, and L-lactate dehydrogenase from pig skeletal muscle a redox reaction takes place between the pyruvate moiety and the dihydropyridine ring of the analog. This reaction is shown to be intramolecular by competition experiments with pyruvate. Degradation of the reaction products reveals that the carbon-2 atom of the formed lactate side chain exhibits D configuration in each of these cases studied.