中国强毒力赖型钩端螺旋体外膜蛋白基因的克隆表达及对大肠杆菌活力的影响  

Cloning expression and toxic effect on the host bacterial viability of an outer envelope protein from the strong virulent leptospira lai in China

作　　者：鲍朗[1] 晏菊芳[1] 胡昌华[1] 谢勇恩[1] 邱洪宇[1] 张会东[1] 

机构地区：[1]华西医科大学病理生理学教研室感染免疫研究室,四川成都610041

出　　处：《中国病理生理杂志》2001年第8期705-709,共5页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目 (No .30 0 70 6 70 );四川省学术技术带头人培养基金资助项目

摘　　要：目的 :构建表达致病性赖型 0 17株钩端螺旋体OmpL1外膜蛋白的真核 -原核穿梭表达载体 ,并在原核细胞中表达出目的蛋白。方法 :用PCR方法从 0 17株钩体基因组中钓出OmpL1蛋白基因 ,酶切纯化后与质粒pBK -CMV连接 ,通过电泳、限制性内切酶分析及PCR鉴定筛选出正确重组质粒。重组质粒在大肠杆菌中诱导表达后提取总蛋白以SDS -PAGE检测表达情况 ,同时监测目的蛋白表达前后各时段宿主菌OD6 0 0值的变化。结果 :筛选出 5株带重组质粒菌 ,其中有 4株能在大肠杆菌中表达 37kD的特异蛋白 ,而且随着该外源蛋白的表达 ,宿主菌生长各时段的OD6 0 0值下降。结论 :成功地构建了钩体OmpL1蛋白的穿梭表达质粒 ,并在大肠杆菌中表达出OmpL1融合蛋白 ,该异源蛋白的表达导致宿主菌的活力降低。本工作为OmpL1蛋白用于钩体病诊断。AIM: Construction of an eukaryote- E. coli shuttle expressing recombinant plasmid which expresses OmpL1 envelope protein of pathogenic Leptospira, serovar Lai strain 017. METHODS: The OmpL 1 gene was amplified by PCR from the leptospiral genome. Then it was cut with restriction enzymes and ligated to the plasmid pBK-CMV. The correct recombinant plasmid was screened out with analysis of restriction enzymes and PCR. After inducing the E. coli baring recombinant plasmid with IPTG,the complete protein of the bacteria was extracted for SDS-PAGE. At the same time, OD600 of the host bacteria was examined at different time after inducing or uninducing with IPTG. RESULTS: Five strains E. coli containing proper recombinant plasmids were screened out. Four strains E. coli expressed a new protein with a weight of 37 kD among them. With the expression of the heterogenous protein,the OD600 of the host bacteria decreased. CONCLUSION: The shuttle expressing plasmid of the OmpL 1 gene of strong virulent Leptospira strain 017 was successfully constructed. Furthermore,the recombinant plasmid expressed the expected OmpL 1 fusion protein in E. coli and the expression of the heterogenous protein had toxic effect on the host bacteria. This work was important for the future research of OmpL1 protein which relates to the diagnosis,new vaccine preparing and the pathogenic mechanism of leptospirosis.

关 键 词：钩端螺旋体 基因表达 质粒 克隆 大肠杆菌 外膜蛋白 

分 类 号：R377.5[医药卫生—病原生物学]