β-半乳糖苷酶重组大肠杆菌诱导表达条件的研究  

Studies on Induction Conditions of Recombinant Escherichia coli Encoding β-Galactosidase

作　　者：陈卫[1] 张灏[1] 葛佳佳[1] 丁霄霖[1] 

机构地区：[1]江南大学食品学院,江苏无锡214036

出　　处：《乳业科学与技术》2002年第3期1-4,共4页JOURNAL OF DAIRY SCIENCE AND TECHNOLOGY

摘　　要：β-半乳糖苷酶常用于牛奶中乳糖的水解。来源于嗜热脂肪芽孢杆菌的高温β-半乳糖苷酶基因经克隆后转入大肠杆菌T7表达系统得到成功表达。在SOB培养基上分别以IPTG和乳糖为诱导剂,对重组菌的诱导时机、诱导浓度和诱导长度进行研究,β-半乳糖苷酶比酶活分别达到11.5 U/mg和7.7 U/mg,比酶源菌提高90和60倍。β-galactosidase can be used to hydrolyze lactose of milk into glucose and galactose. Athermostable β-galactosidase gene bgaB from Bacillus stearothermophilus was cloned and successfully expressed in E. coli T7 expression system. The optimum induction conditions, i.e. induction time, inducer concentration and induction length were studied on SOB media by IPTG and Lactose as inducers. The specific enzyme activity reached 11.5 and 7.7 U/mg protein, 90 and 60 times higher than that of original strain, respectively.

关 键 词：Β-半乳糖苷酶 重组大肠杆菌 嗜热脂肪芽孢杆菌 基因克隆 诱导条件 

分 类 号：TQ925[轻工技术与工程—发酵工程] Q78[生物学—分子生物学]