中国白酒酿造物料中分离的酵母菌株在不对称羰基还原中的应用

Asymmetric Ketone Reduction Using Targeted Yeast Collections Isolated from Chinese Liquor Pits

中国白酒窖的酿造物料中含有大量的细菌、酵母及霉菌菌株.为了研究其中的代表性酵母菌株在不对称羰基还原中的应用,利用5种不同的羰基化合物为底物,对保存于中国科学院成都生物研究所中国白酒酿造微生物菌种库中的部分酵母菌株进行了筛选.结果表明大多数菌株都具有羰基还原酶活力,绝大多数符合Prelog规则,其中部分菌株还具有优秀的立体选择性,在药物手性中间体合成应用中具有一定的应用潜力:例如其中拟威尔酵母属Williopsis sp.2.045在转化底物3,5-双三氟甲基苯乙酮时的转化率以及S构型产物光学纯度均高于99%;红酵母属Rhodotorula sp.2.154在转化底物N-甲基-3-羰基-3-(2-噻吩)丙酰胺时的转化率及S构型产物光学纯度达到了95%和99%.这些发现也表明白酒酿造物料中含有大量具有羰基还原酶活力的生物资源,因此中国白酒酿造微生物菌种库可作为不对称羰基还原研究中的储备酶库,直接对目标库中的菌种进行筛选能够大幅度提高菌株选择的效率.

Plenty of bacteria, yeasts, molds have been found in Chinese liquor pits. In order to investigate the applications of specific yeasts on ketone reduction, we screened some yeast strains in the Yeast Library of Chinese Liquor Pits in Chengdu Institute of Biology, Chinese Academy of Sciences, using five carbonyl compounds as potential substrates. The results indicated that the majority of the strains were capable of ketone reduction, and most of them obeyed the Prelog’s rule. Some of the strains showed excellent stereo-selectivity, indicating high application potential in chiral drug intermediates production. For example, Williopsis sp. 2.045 transfered 3,5-bis（trifluoromethyl）-acetophenone into （S）-3,5-bis（trifluoromethyl）-1-phenethanol with over 99% yield and ee; Rhodotorula sp. 2.154 changed N-methyl-3-oxo-3-（thiophen-2-yl）propanamide into （S）-3-hydroxy-N-methyl-3-（thiophen-2-yl）propanamide with a yields of 95% and 99% ee. The results suggested that Chinese liquor pits contains lots of bioresources with high ketone reducing activity. It could be used as a targeted library in the screening of microbes with ketone reductase activity, which can highly improve the efficiency of strain screening.