Oxidoreductases and Hydroxynitrilase Lyases: Complementary Enzymatic Technologies for Chiral Alcohols



Biocatalytic processes are useful methods for the production of chiral intermediates. As an example, alcohol dehydrogenases are applied for the production of chiral alcohols by asymmetric reduction of prochiral ketones. From this class of enzymes alcohol dehydrogenase from Lactobacillus brevis will be described with respect to its industrial application. The process for the production of methyl (R)-3-hydroxybutyrate using this enzyme is discussed in more detail. The application of alcohol dehydrogenases can be limited by the commercial availability of the starting material as, for instance, in the case of the synthesis of chiral α-hydroxy acids. For these products asymmetric addition of hydrocyanic acid to aldehydes catalyzed by hydroxynitrile lyases such as (S)-oxynitrilase from Manihot esculenta is a complementary approach. Also, this enzyme will be characterized in more detail with respect to its industrial production and application.