Essential amino acid residues and catalytic mechanism of trans-epoxysuccinate hydrolase for production of meso-tartaric acid

Abstract

This study aimed to discuss the essential amino acid residues and catalytic mechanism of transepoxycussinate hydrolase from Pseudomonas koreensis for production of meso-tartaric acid. ResultsThe optimum conditions of the enzyme were 45°C and pH 9.0, respectively. It was strongly inhibited by Zn 2+ , Mn 2+ and SDS. Michaelis-Menten enzyme kinetics analysis gave a K m value of 3.50 mM and a k cat of 99.75 s − 1 , the EE value was higher than 99.9%. Multiple sequence alignment and homology modeling showed that the enzyme belonged to MhpC superfamily and had a typical α/β hydrolase folding structure. Site-directed mutagenesis indicated H34,