乳糖诱导γ-ggt基因在大肠杆菌中的表达  

Expression of γ-Glutamyl Transpeptidase(γ-ggt)from pET Plasmid Using Lactose as Inducer

作　　者：施林妹[1] 王东明[1] 占扎君[2] 梅献山 

机构地区：[1]丽水职业技术学院环境工程分院,浙江丽水323000 [2]浙江工业大学,浙江杭州310032 [3]丽水市梅峰茶叶有限公司,浙江丽水323000

出　　处：《药物生物技术》2010年第4期287-290,316,共5页Pharmaceutical Biotechnology

基　　金：丽水市科技局校企合作项目

摘　　要：以重组大肠杆菌γ-谷氨酰转肽酶蛋白表达宿主菌株BL21(DE3)(pET28/γ-ggt)作为研究对象,借助SDS-PAGE分析方法,对于用乳糖诱导由T7lac启动子控制的重组目的产物的表达规律进行了优化研究。分析比较了诱导的起始阶段、所需的乳糖浓度和诱导持续时间等参数对重组产物表达的影响。实验结果表明,对于T7lac启动子控制的重组目的产物,乳糖可以作为诱导剂;在对诱导条件进行优化控制的前提下,乳糖诱导目的产物的绝对表达量虽然不及IPTG,但相对成本却比IPTG低得多,且没有毒性。研究结果为乳糖作为诱导剂应用于重组大肠杆菌γ-谷氨酰转肽酶工业化生产提供了一定的参考。The optimization of expression of the cloned y-glutamyl transpeptidase（y-ggt）gene in Esche- richia coli strain BL21 （DE3） by using lactose as the inducer was reported in this paper. It was found that expression level of y-ggt achieved the highest after the BL21 （DE3） was induced for 4 h with lactose 1 g/L begining from strain density of OD600 = 0.9. The expression level of y-ggt protein was about 15.2% of the total cellular proteins. The inducing efficiency of lactose was lower than that as IPTG （i- sopropyl-β-D-thiogalactopyranoside）, but because of the toxicity and the high cost of the latter, lactose is a promising inducer in the lac-promotor based expression system.

关 键 词：y-谷氨酰转肽酶 原核表达 乳糖 IPTG 

分 类 号：Q7[生物学—分子生物学]