Expression, purification and characterization of a thermostable leucine dehydrogenase from the halophilic thermophile Laceyella sacchari.

Abstract

A potential thermotolerant L-leucine dehydrogenase from Laceyella sacchari (Ls-LeuDH) was over-expressed in E. coli, purified and characterized. Ls-LeuDH had excellent thermostability with a specific activity of 183U/mg at pH 10.5 and 25°C. It retained a high activity in 200mM carbonate buffer from pH 9.5 to 11. The optimal temperature for Ls-LeuDH was 60°C. It is the first time that a thermostable and highly active LeuDH originating from L. sacchari has been characterized. It may be useful for medical and pharmaceutical applications.