A Kinetic Study of Saccharopine Dehydrogenase Reaction

Abstract

Kinetic studies were carried out on saccharopine [ɛ‐N‐(l‐glutaryl‐2)‐l‐lysine] dehydrogenase which catalyzed a reversible reaction according to the following equation. Saccharopine + NAD++ H2O ⇌ lysine +α‐ketoglutarate + NADH + H+. Initial velocity kinetics of the reverse direction showed that the saccharopine dehydrogenasecatalyzed reaction was consistent with a mechanism that the addition and release of reactants to and from the enzyme follow an obligatory order. The product inhibition studies in the forward direction also revealed kinetic patterns consistent with the ordered mechanism where the sequence of addition of substrates being NAD+ and saccharopine, and that of release of products being lysine, α‐ketoglutarate and NADH. The various kinetic parameters determined at pH 6.8 and 22° are also described. Copyright © 1970, Wiley Blackwell. All rights reserved