Evidence for the coenzymatic nature of a synthetic cofactor involved in the biotin related deaminase systems.

Welhave!reported previously (Christman and Williams, 1952) concerning the synthes of a specific activator for aspartic acid deaminase by the sulfuric acid degradation of carbohydrates. The immediate conclusion arising from this observation was that biotin and adenylic acid could not be constituents of the "coenzyme" although the mode of action of the enzyme system and its activators remained to be elucidated. Evidence was presented in this same report which showed that this carbohydrate degradation product was identical in physico-chemical behavior to the substance present in yeast and liver extracts which has been designated by Lichstein (1950) to be the coenzyme of aspartic acid, seine, and threonine deaminases, and succinic acid and oxaacetic acid decarboxylase. It is the purpose of this communication to resolve some of the speculation concerning these systems, and to present evidence that this synthetic material behaves as the coenzyme of the deaminases of aspartic acid, serine, and threonine. Evidence also will be presented to the effect that biotin and adenylic acid also are involved intimately in these same systems, albeit unrelated to the chemical structure of the coenzyme.