Alcohol Dehydrogenases Catalyze the Reduction of Thioesters

Alcohol dehydrogenases are well-established catalysts for various reduction reactions. However, the reduction of carboxylic acid derivatives has not yet been reported with these enzymes. In this contribution, we demonstrated that carboxylic acid thioesters could be readily reduced by a range of alcohol dehydrogenases, albeit at significantly reduced rates relative to those observed for corresponding ketones. A molecular explanation, especially for the lower turnover rates for thioesters relative to those obtained for ketones, is presented, as is a preliminary substrate scope.