32345-77-0Relevant academic research and scientific papers
Highly Efficient Deracemization of Racemic 2-Hydroxy Acids in a Three-Enzyme Co-Expression System Using a Novel Ketoacid Reductase
Xue, Ya-Ping,Wang, Chuang,Wang, Di-Chen,Liu, Zhi-Qiang,Zheng, Yu-Guo
, p. 1 - 13 (2018/04/26)
Enantiopure 2-hydroxy acids (2-HAs) are important intermediates for the synthesis of pharmaceuticals and fine chemicals. Deracemization of racemic 2-HAs into the corresponding single enantiomers represents an economical and highly efficient approach for synthesizing chiral 2-HAs in industry. In this work, a novel ketoacid reductase from Leuconostoc lactis (LlKAR) with higher activity and substrate tolerance towards aromatic α-ketoacids was discovered by genome mining, and then its enzymatic properties were characterized. Accordingly, an engineered Escherichia coli (HADH-LlKAR-GDH) co-expressing 2-hydroxyacid dehydrogenase, LlKAR, and glucose dehydrogenase was constructed for efficient deracemization of racemic 2-HAs. Most of the racemic 2-HAs were deracemized to their (R)-isomers at high yields and enantiomeric purity. In the case of racemic 2-chloromandelic acid, as much as 300 mM of substrate was completely transformed into the optically pure (R)-2-chloromandelic acid (> 99% enantiomeric excess) with a high productivity of 83.8 g L?1 day?1 without addition of exogenous cofactor, which make this novel whole-cell biocatalyst more promising and competitive in practical application.
An enzyme library approach to biocatalysis: Development of nitrilases for enantioselective production of carboxylic acid derivatives
DeSantis, Grace,Zhu, Zuolin,Greenberg, William A.,Wong, Kelvin,Chaplin, Jenny,Hanson, Sarah R.,Farwell, Bob,Nicholson, Lawrence W.,Rand, Cynthia L.,Weiner, David P.,Robertson, Dan E.,Burk, Mark J.
, p. 9024 - 9025 (2007/10/03)
The discovery, from Nature, of a large and diverse set of nitrilases is reported. The utility of this nitrilase library for identifying enzymes that catalyze efficient production of valuable hydroxy carboxylic acid derivatives is demonstrated. Unprecedented enantioselectivity and substrate scope are highlighted for three newly discovered and distinct nitrilases. For example, a wide array of (R)-mandelic acid derivatives and analogues were produced with high rates, yields, and enantiomeric excesses (95-99% ee). We also have found nitrilases that provide direct access to (S)-phenyllactic acid and other aryllactic acid derivatives, again with high yields and enantioselectivities. Finally, different nitrilases have been discovered that catalyze enantiotopic hydrolysis of 3-hydroxyglutaronitrile to afford either enantiomer of 4-cyano-3-hydroxybutyric acid with high enantiomeric excesses (>95% ee). The first enzymes are reported that effect this transformation to furnish the (R)-4-cyano-3-hydroxybutyric acid which is a precursor to the blockbuster drug Lipitor. Copyright
Process for preparing optically active cyanohydrins and secondary products
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, (2008/06/13)
The present invention relates to a process for preparing optically active cyanohydrins of the formula (II), by reacting an aldehyde of the formula (I) with HCN in a water-immiscible organic solvent in the presence of water, in the absence or presence of a buffer, in the presence of a (R)-hydroxynitrile lyase, where X, Y and Z in formula (II) have the same meaning as in formula (I), independently of each other are identical or different and are H, F, Cl, Br, I, OH, O(C1-C4-alkyl), OCOCH3, NHCOCH3, NO2 or C1-C4-alkyl.
