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Bulut D, Duangdee N, Gröger H, Berkessel A, Hummel W. Screening, Molecular Cloning, and Biochemical Characterization of an Alcohol Dehydrogenase from Pichia pastoris Useful for the Kinetic Resolution of a Racemic β-Hydroxy-β-trifluoromethyl Ketone. Chembiochem 2016; 17:1349-58. [PMID: 27123855 DOI: 10.1002/cbic.201600101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Indexed: 12/28/2022]
Abstract
The stereoselective synthesis of chiral 1,3-diols with the aid of biocatalysts is an attractive tool in organic chemistry. Besides the reduction of diketones, an alternative approach consists of the stereoselective reduction of β-hydroxy ketones (aldols). Thus, we screened for an alcohol dehydrogenase (ADH) that would selectively reduce a β-hydroxy-β-trifluoromethyl ketone. One potential starting material for this process is readily available by aldol addition of acetone to 2,2,2-trifluoroacetophenone. Over 200 strains were screened, and only a few yeast strains showed stereoselective reduction activities. The enzyme responsible for the reduction of the β-hydroxy-β-trifluoromethyl ketone was identified after purification and subsequent MALDI-TOF mass spectrometric analysis. As a result, a new NADP(+) -dependent ADH from Pichia pastoris (PPADH) was identified and confirmed to be capable of stereospecific and diastereoselective reduction of the β-hydroxy-β-trifluoromethyl ketone to its corresponding 1,3-diol. The gene encoding PPADH was cloned and heterologously expressed in Escherichia coli BL21(DE3). To determine the influence of an N- or C-terminal His-tag fusion, three different recombinant plasmids were constructed. Interestingly, the variant with the N-terminal His-tag showed the highest activity; consequently, this variant was purified and characterized. Kinetic parameters and the dependency of activity on pH and temperature were determined. PPADH shows a substrate preference for the reduction of linear and branched aliphatic aldehydes. Surprisingly, the enzyme shows no comparable activity towards ketones other than the β-hydroxy-β-trifluoromethyl ketone.
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Affiliation(s)
- Dalia Bulut
- Institute of Molecular Enzyme Technology, Heinrich Heine University of Düsseldorf, Research Centre Jülich, Wilhelm-Johnen-Strasse, 52426, Jülich, Germany.,Faculty of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Nongnaphat Duangdee
- Department of Chemistry, Cologne University, Greinstrasse 4, 50939, Köln, Germany
| | - Harald Gröger
- Faculty of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615, Bielefeld, Germany
| | - Albrecht Berkessel
- Department of Chemistry, Cologne University, Greinstrasse 4, 50939, Köln, Germany
| | - Werner Hummel
- Institute of Molecular Enzyme Technology, Heinrich Heine University of Düsseldorf, Research Centre Jülich, Wilhelm-Johnen-Strasse, 52426, Jülich, Germany. .,Faculty of Chemistry, Bielefeld University, Universitätsstrasse 25, 33615, Bielefeld, Germany.
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