期刊论文

中文

湖南农业大学学报(自然科学版)

1007-1032

2011

37

3

267-270

10.3724/SP.J.1238.2011.00267

30871572:国家自然科学基金 973;2008CB117007:国家重点基础研究发展计划（973计划） 07WD22:湖南农业大学人才科学基金项目

本校为第一机构

将来源于Escherichia coli DH5α的γ-谷氨酰转肽酶基因克隆到高表达质粒pET-32α中,并转化E·coli BL21,构建茶氨酸生物合成的基因工程菌。工程菌在温度为20℃,OD600nm为1.5,IPTG浓度为0.1mmol/L,培养基初始pH为7的条件下,诱导培养6h,γ-谷氨酰转肽酶的酶活力达（4.41±0.17）U/mL,大约是出发菌株E·coli DH5α的18.4倍。直接以工程菌为催化剂,在200mmol/L谷氨酰胺、1.5mol/L乙胺盐酸盐、pH10、20℃的条件下,反应6h,茶氨酸合成量达12.6mg/mL,L-谷氨酰胺转化率为41.05%。

The γ-Glutamyltranspeptidase gene from Escherichia coli DH5ct was cloned in pET-32a vector and expressed in Escherichia coli BL21. When the recombinant strain grew at pH 7 to obtain the OD600nm of 1.5 and induced with 0.1 mmol/L IPTG at 20℃ for 6 h, the activity of γ-Glutamyltranspeptidase was （4.41-4-0.17） U/mL, about 18.4 times than that ofEscherichia coli DHSct. Under the catalysis of cells of the genetically engineered strain and under the pH 10, the temperature of 20℃ and the incubation time of 6 h, the yield of theanine from L-Gin （...