Zhu Yibo, Hu Fagen, Zhu Yingyue, Wang Limei, Qi Bin
School of Biotechnology and Food Engineering, Changshu Institute of Technology, Changshu, 215500, Jiangsu, People's Republic of China,
Biotechnol Lett. 2015 Jun;37(6):1233-41. doi: 10.1007/s10529-015-1778-4. Epub 2015 Feb 4.
The Tyr52 residue of D-lactate dehydrogenase (D-LDH) from Lactobacillus pentosus was replaced with small hydrophobic residues and overexpressed in E. coli BL21 (DE3) to enhance 3-phenyllactic acid (PLA) synthesis by whole-cell catalyst.
Escherichia coli pET-28a-d-ldh produced 12.2 g PLA l(-1) in 3 h, with a molar conversion rate of 61 %, while E. coli pET-28a-d-ldh (Y52V) produced 15.6 g PLA l(-1), with a molar conversion rate of 77 %. This study demonstrates the feasibility of using engineered E. coli for PLA production from phenylpyruvate (PPA) and showed that site-directed mutagenesis of d-ldh markedly improved PLA yield and substrate conversion rate.
This biocatalytic system is a promising platform for PLA production from PPA.
将戊糖乳杆菌D-乳酸脱氢酶（D-LDH）的Tyr52残基替换为小的疏水残基，并在大肠杆菌BL21（DE3）中过表达，以通过全细胞催化剂提高3-苯乳酸（PLA）的合成。
大肠杆菌pET-28a-d-ldh在3小时内产生12.2 g PLA l(-1)，摩尔转化率为61%，而大肠杆菌pET-28a-d-ldh（Y52V）产生15.6 g PLA l(-1)，摩尔转化率为77%。本研究证明了使用工程化大肠杆菌从苯丙酮酸（PPA）生产PLA的可行性，并表明d-ldh的定点诱变显著提高了PLA产量和底物转化率。
该生物催化系统是一个有前途的从PPA生产PLA的平台。
