Facile synthesis of chiral 2-hydroxy acids catalyzed by a stable duck ε-crystallin with endogenous l-lactate dehydrogenase activity

Abstract

Duck ε-crystallin, an abundant structural protein in lenses of some avian species, was shown to possess a genuine and stable l-lactate dehydrogenase ( l-LDH, EC 1.1.1.27) activity suitable for the application to enzyme technology as a catalyst for the synthesis of chiral α-hydroxy acids. Two pharmaceutically important intermediates, 2-hydroxy acids ( S)-2-hydroxybutanoic acid ( S)-2-hydroxypentanoic acid) have been synthesized in high yields and Optical purity utilizing an in situ NADH regeneration system of duck ε-crystallin coupled with formate/formate dehydrogenase. This enzyme system is also shown to offer some advantages over the conventional l-LDH sources from several mammalian species.