摘要
L-茶氨酸作为一种非天然氨基酸对人体健康具有多方面的功效,其作为食品饮品添加剂和制药原料的需求量日益增加。本文以安全菌株Bacillus subtilis 168作为宿主菌,表达生产B.pumilus来源的γ-谷氨酰转肽酶(GGT)。结果显示,该来源GGT成功在B.subtilis 168中实现了胞外分泌表达。最后,通过关键转化条件优化,并结合批次流加策略,该重组GGT能够在16 h催化合成50.8 g/L的L-茶氨酸,该结果可以和已报道的以大肠杆菌作为宿主菌表达GGT并催化合成L-茶氨酸的产量相媲美。
L-theanine,is a nonproteic amino acid which recently has an increasing demand as it is applied in food and pharmaceutical industries.In this study,a GRAS(Generally Recognized As Safe)strain Bacillus subtilis 168 was used as the host to produce a novelγ-glutamyl transferase(GGT)from B.pumilus ML413.The enzyme produced was applied to L-theanine synthesis.Subsequently,glutamine conversion efficiency with the GGT was optimized.Finally,for the improved L-theanine production,a fed-batch strategy was introduced and the maximum titer of L-theanine reached 50.8 g/L at 16 h.This titer could be comparable to the efficient but toxic GGT producer recombinant E.coli.
作者
KOMERA Irene
杨套伟
张显
饶志明
徐美娟
KOMERA Irene;YANG Taowei;ZHANG Xian;RAO Zhiming;XU Meijuan(School of Biotechnology,Jiangnan University,Wuxi 214122,China)
出处
《食品与生物技术学报》
CAS
CSCD
北大核心
2019年第10期67-71,共5页
Journal of Food Science and Biotechnology
基金
国家863计划项目(2015AA021004)
江苏省杰出青年科学基金项目(BK20150002)
中国博士后科学基金项目(2015M570407)
中央高校基本科研业务费专项资金(JUSRP51708A)
111引智计划(111-2-06)
江苏省现代发酵工业协同创新中心项目
