Characterization of a newly synthesized epoxide hydrolase and its application in racemic resolution of (R,S)-epichlorohydrin

In the current study, an epoxide hydrolase (EH) gene from Rhodosporidium toruloides was synthesized and expressed in Escherichia coli. After purification, we found that the optimal pH and temperature of this enzyme were 7.5 and 35 °C, respectively. The recombinant EH obtained in this study was temperature-sensitive and the activity decreased significantly above 45 °C. The values of apparent Km and Vmax were 0.5953 mol/l and 0.0105 mol/(L·min). In addition, enantiomeric excesses value of (R)-epichlorohydrin could reach 100% after 40-min reaction. Moreover, this EH showed a broad substrates specificity toward epoxides. To the best of our knowledge, this is the first time to report the application of R. toruloides EH in racemic resolution of (R,S)-epichlorohydrin to produce (R)-epichlorohydrin.

A newly synthesized epoxide hydrolase was obtained and characterized. This recombinant epoxide hydrolase could be used in racemic resolution of (R,S)-epichlorohydrin to produce (R)-epichlorohydrin.Figure optionsDownload as PowerPoint slideHighlights
► R. toruloides CBS14 EH gene was synthesized and expressed in E. coli.
► The recombinant EH showed a broad substrate specificity toward epoxides.
► The enantiomeric excess value of (R)-epichlorohydrin was 100%.
► This recombinant EH is potential for production of (R)-epichlorohydrin and diols.