乳糖诱导耐热木聚糖酶基因在大肠杆菌中表达  

Optimization of expression of recombinant thermo-stable xylanase produced by recombinant E.coli 1020

作　　者：朱孝霖[1] 孙雷[1] 李环[1] 韦萍[1] 

机构地区：[1]南京工业大学制药与生命科学学院,南京210009

出　　处：《生物加工过程》2005年第4期54-57,65,共5页Chinese Journal of Bioprocess Engineering

基　　金：国家973计划项目(编号2003CB7160004)资助

摘　　要：考察乳糖代替IPTG诱导耐热木聚糖酶基因在重组大肠杆菌BL21中表达的可行性。分别以IPTG和乳糖作为诱导剂,对诱导时机、诱导剂浓度、诱导持续时间等主要因素进行了分析比较。结果表明,当菌体生长至发酵液吸光值OD600达1.3时加入乳糖其终浓度达29.2 mmol/L,37℃,持续诱导9.5 h,木聚糖酶活力达到最高,为3 587.5U,是IPTG优化条件下持续诱导7 h达到的最高酶活的2.07倍,而成本只有IPTG的1/204。Attempt to use lactose instead of IPTG inducing expression of thermo-stable xylanase by the recombinant strain E. coli BL21. The effects of the main factors of induction, such as, biomass of bacteria grown when the inducer was added initially, final concentrations of the inducer in the broth, and the duration of induction were investigated. When the absorptance OD600 of broth given by the recombinant stain up to 1.3, lactose was added so as to the final concentration to 29.2 mmol/L,and induction was conducted for 9.5 h at 37℃, the xylanase activity of the cells harvested reached the maximum value as 3 587.5 U, which was 2.07 times as much as that given by the recombinant strain induced by IPTG for 7 h, but the cost of lactose used decreased by 204 times as much as that of IPTG.

关 键 词：耐热木聚糖酶 乳糖 诱导表达 SDS-PAGE 

分 类 号：TQ920.1[轻工技术与工程—发酵工程]