nicotinamide adenine dinucleotide ( nad ) dependent urocanase ( 4'-imidazolone-5'-propionate hydro-lyase , ec 4.2.1.49 ) from pseudomonas putida was found to catalyze an exchange reaction between solvent and the 4'-hydrogen of urocanate or imidazolepropionate at a rate faster than that of overall deuterium was compared to unlabeled urocanate as a substrate , no isotope rate effect was noted .
C0042053
urocanase
C0020239
hydro-lyase