Huang Jinlong, Zhang Yun, Hu Yunfeng
Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, People's Republic of China.
University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
Appl Biochem Biotechnol. 2016 Dec;180(8):1467-1481. doi: 10.1007/s12010-016-2180-y. Epub 2016 Jun 30.
Chiral lactic acid and its ester derivatives are crucial building blocks and platforms in the generation of high value-added drugs, fine chemicals and functional materials. Optically pure D-lactic acid and its ester derivatives cannot be directly generated from fermentation and are quite expensive. Herein, we identified, heterologously expressed and functionally characterized one Bacillus esterase BSE01701 from the deep sea of the Indian Ocean. Esterase BSE01701 could enzymatically resolve inexpensive racemic methyl lactate and generate chiral D-methyl lactate. The enantiomeric excess of desired chiral D-methyl lactate and the substrate conversion could reach over 99 % and 60 %, respectively, after process optimization. Notably, the addition of 60 % (v/v) organic co-solvent heptane could greatly improve both the enantiomeric excess of D-methyl lactate and the conversion. BSE01701 was a very promising marine microbial esterase in the generation of chiral chemicals in industry.
手性乳酸及其酯衍生物是生产高附加值药物、精细化学品和功能材料的关键构建单元和平台。光学纯的D-乳酸及其酯衍生物无法通过发酵直接获得，且价格昂贵。在此，我们从印度洋深海中鉴定、异源表达并对一种芽孢杆菌酯酶BSE01701进行了功能表征。酯酶BSE01701能够通过酶法拆分廉价的外消旋乳酸甲酯，生成手性D-乳酸甲酯。经过工艺优化后，所需手性D-乳酸甲酯的对映体过量值和底物转化率分别可达到99%以上和60%以上。值得注意的是，添加60%（v/v）的有机共溶剂庚烷可极大地提高D-乳酸甲酯的对映体过量值和转化率。BSE01701是一种在工业生产手性化学品方面非常有前景的海洋微生物酯酶。
