A novel D-mandelate dehydrogenase used in three-enzyme cascade reaction for highly efficient synthesis of non-natural chiral amino acids

作者：Fan, Chang-Wei; Xu, Guo-Chao; Ma, Bao-Di; Bai, Yun-Peng; Zhang, Jie; Xu, Jian-He^*

来源：Journal of Biotechnology, 2015, 195: 67-71.

DOI：10.1016/j.jbiotec.2014.10.026

• D-Mandelate dehydrogenase
• L-Phenylglycine
• Asymmetric synthesis
• Cascade reaction
• Process optimization

A novel NAD(+)-dependent D-mandelate dehydrogenase was identified from Lactobacillus brevis (LbDMDH). After purified to homogeneity, the optimum pH and temperature for oxidation of D-mandelate were pH 10.0 and 40 degrees C, and the K-m and k(cat) were 1.1 mM and 355 s(-1) respectively. Employing the LbDMDH together with a mandelate racemase from Pseudomonas putida and a leucine dehydrogenase (EsLeuDH) from Exiguobacterium sibiricum, we established a three-step one-pot domino reaction system for preparing chiral L-phenylglycine from racemic mandelic acid with internal cofactor recycling. Under the optimum conditions, 30.4 g rac-mandelic acid (0.2 M) at 1 L scale had been converted into chiral L-phenylglycine, with 96.4% conversion, 86.5% isolation yield, >99% ee(p) and 50.4 g L-1 d(-1) space-time yield.

• 出版日期2015-2-10
• 单位生物反应器工程国家重点实验室; 华东理工大学