L-2-Imidazolidone-4-carboxylic acid is an effective competitive inhibitor of the reaction catalyzed by 5-oxoprolinase, in which 5-oxo-L-proline (L-pyroglutamic acid, L-2-pyrrolidone-5-carboxylic acid, L-5-oxopyrrolidine-2-carboxylic acid) is converted to L-glutamate, with concomitant cleavage of ATP to ADP and orthophosphate. L-2-Imidazolidone-4-carboxylate decreased the rate of metabolism of 5...