Enzymatic synthesis and characterization of N(5)-(carboxymethyl)-L-ornithine and N (6)-(carboxymethyl)-L-lysine.

This report describes the enzyme-catalyzed synthesis, characterization, and chromatographic separation of N(6)-(carboxymethyl)-L-lysine and N(5)-(carboxymethyl)-L-ornithine. The two N (ω) -(carboxyalkyl)amino acids are formed via a reductive condensation between glyoxylate and theε- orδ-amino groups of lysine and ornithine, respectively. Both reactions are catalyzed by the NADPH-dependent enzyme, N(5)-(carboxyethyl)ornithine synthase [EC 1.5.1.24], found in some strains of the lactic acid bacteriumLactococcus lactis subsp.lactis.