Enantioselective esterase activity of an industrial glutaryl acylase

The unexpected esterase activity of an industrial glutaryl acylase was investigated. Glutaryl esters of a series of primary and secondary alcohols as well as of phenols were all efficiently hydrolyzed, the only exception being the sterically hindered glutarate of thymol. The enantioselectivities of the acylase, which were evaluated with three of these substrates, were quite low (E values ranging between 1.9 and 7.2), but were significantly improved by substrate and/or solvent engineering. Enantiomerically enriched hydrolyzed alcohols and unreacted glutarates can be easily separated by selective extraction, thus avoiding chromatographic steps.

An industrial glutaryl-7-aminocephalosporanic acid acylase (GAR) showed a significant esterases activity. Kinetic resolutions of racemic alcohols (e.g. 1) were performed and the enantioselectivity could be improved by substrate or solvent engineering.Figure optionsDownload as PowerPoint slide