Production of a novel opine dehydrogenase

Abstract

Opine dehydrogenases are a family of NAD(P)H dependent oxidoreductases, which catalyze the reductive condensation of an α amino group from an amino acid with an αketo acid during anaerobic glycolysis by regenerating NAD. They are widespread in cephalopods and mollusks. Opines are associated with crown gall tumor pathogenesis caused by A. tumefaciens providing nutrients to the pathogen, and novel opine compounds acting as metallophores have been identified. Besides, opine-type secondary amine dicarboxylic acids are chiral intermediates of angiotensin-converting enzyme inhibitors. A novel enzyme originating from an extremophile bacterium, with assumed opine dehydrogenase function was successfully expressed in Escherichia coli STAR cells and purified by affinity chromatography. Molecular mass determined by SDS-PAGE was approximately 40 kDa. The activity was measured by using pyruvate and alanine as substrates, by which proved that it has opine dehydrogenase activity.