重组大肠杆菌全细胞催化合成L-苯乳酸  

Synthesis of L-phenyllactic acid catalyzed by recombinant Escherichia coli whole cell biotransformation

作　　者：邵宇 张显 胡孟凯 魏玉霞[1] 杨套伟 徐美娟 邵明龙 高敏杰 饶志明 SHAO Yu;ZHANG Xian;HU Mengkai;WEI Yuxia;YANG Taowei;XU Meijuan;SHAO Minglong;GAO Minjie;RAO Zhiming(Key Laboratory of Industrial Biotechnology,Ministry of Education(Jiangnan University),Wuxi 214122,China)

机构地区：[1]工业生物技术教育部重点实验室(江南大学),江苏无锡214122

出　　处：《食品与发酵工业》2021年第14期1-8,共8页Food and Fermentation Industries

基　　金：国家重点研发计划项目(2020YFA0908300);国家自然科学基金项目(32071470);宁夏回族自治区重点研发计划项目(2020BFH01001);山东省重点研发项目(2019JZZY020605);福建省水产功能性饲料及养殖环境调控重点实验室开放课题(FACE20200003)。

摘　　要：L-苯乳酸是一种天然抑菌物质,对多种病原微生物有光谱抑制作用,有望成为一种新型生物防腐剂。通过构建多酶级联催化反应体系,提高大肠杆菌合成L-苯乳酸的能力。利用共表达L-氨基酸脱氨酶和苯丙酮酸还原酶并偶联葡萄糖脱氢酶进行辅酶再生,建立一种新型L-苯乳酸生物合成方法。各基因成功在大肠杆菌中表达,并对全细胞转化条件进行优化,最适转化条件为反应温度30℃,初始pH值为8.0,底物苯丙氨酸30 g/L,菌体OD_(600)为30,辅底物葡萄糖1倍摩尔当量,转化反应12 h,共生成L-苯乳酸21.39 g/L,摩尔转化率为71.33%。提供了一种简洁、高效的生物催化方法,为实现规模化生产奠定了基础。L-Phenyllactic acid is a natural antibacterial substance,which has a spectral inhibitory effect on a variety of pathogenic microorganisms.It is expected to become a new type of biological preservative.A multi-enzyme cascade catalytic reaction system was constructed to improve the ability of L-phenyllactic acid synthesis by Escherichia coli whole cell.A new L-phenyllactic acid biosynthesis method was established by co-expressing L-amino acid deaminase and phenylpyruvate reductase coupled with glucose dehydrogenase for coenzyme regeneration.The genes were successfully expressed in E.coli.The whole cell transformation conditions were optimized.The optimal transformation conditions were reaction at 30℃,initial pH 8.0,substrate phenylalanine of 30 g/L,OD_(600) of 30,and auxiliary substrate glucose of one-time molar equivalent,conversion reaction time of 12 h.A total of 21.39 g/L of L-phenyllactic acid was produced,and the molar conversion rate was 71.33%.A simple and efficient biocatalysis method is provided,which lays the foundation for the realization of large-scale production.

关 键 词：L-苯乳酸 L-氨基酸脱氨酶 苯丙酮酸还原酶 辅酶循环 全细胞转化 

分 类 号：TQ245.1[化学工程—有机化工] TQ426.97