Prospecting for efficient enantioselective epoxide hydrolases

Epoxide hydrolases (EHs) from microbial sources have recently been recognized as a versatile biocatalytic tool for the synthesis of enantiomerically pure epoxides and vicinal diols. Keeping in mind the potential of these compounds in pharmaceutical, agrochemical and flavour industries, a range of epoxide substrates have been analyzed using epoxide hydrolase as the catalyst. Enzymatic catalysis is often characterized by exquisite selectivity coupled with limited substrate scope. Hence, research efforts have been on to engineer known EHs for better enantioselectivity and to find novel enantioselective EHs with a wide substrate scope from culturables, non-culturables or from the genome database. Some of the results obtained are promising in terms of the practical utility of these enzymes in the asymmetric hydrolysis of epoxides.