Unexpected stereorecognition in nitrilase-catalyzed hydrolysis of beta-hydroxy nitriles
Sukanta Kamila1, Dunming Zhu, Edward R Biehl
1Department of Chemistry, Southern Methodist University, Dallas, Texas 75275, USA.
Abstract:
Biocatalytic enantioselective hydrolysis of beta-hydroxy nitriles to corresponding (S)-enriched beta-hydroxy carboxylic acids has been achieved for the first time by an isolated nitrilase bll6402 from Bradyrhizobium japonicum USDA110. This offers a new "green" approach to optically pure beta-hydroxy nitriles and beta-hydroxy carboxylic acids. The observed remote stereorecognition is surprising because this nitrilase shows no enantioselectivity for the hydrolysis of alpha-hydroxy nitriles such as mandelonitrile.
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