口蹄疫病毒2B蛋白基因的原核表达及其表达产物的细胞毒性分析

Expression of nonstructural protein 2B gene of foot-and-mouth disease virus in Escherichia coli and analysis of its cytotoxicity

为了实现口蹄疫病毒非结构蛋白基因2B在原核表达系统中的可溶性表达并分析其生物学活性,采用SUMO融合技术构建带有2B基因的pSMK-2B重组质粒,然后分别把此重组质粒转入大肠杆菌菌株BL21(DE3)和C43(DE3)中进行诱导表达。通过对比2B蛋白在普通大肠杆菌BL21(DE3)中和抗毒性蛋白的大肠杆菌C43(DE3)中的表达情况,分析了表达蛋白的细胞毒性作用。结果显示,口蹄疫病毒非结构蛋白基因2B只在大肠杆菌菌株C43(DE3)中实现了可溶性表达,表达产物能抑制表达菌的增殖;进一步证实了2B蛋白对大肠杆菌菌株BL21(DE3)和C43(DE3)存在不同水平的毒性作用。本研究获得的可溶性2B蛋白将为其生物学功能的研究提供前提条件。

To make soluble expression of nonstructural protein 2B gene of foot-and-mouth disease virus in the prokaryotic expression systems, and to investigate its biological activities, a recombinant vector pSMK-2B containing 2B gene was constructed by SUMO fusion technology, and then transformed into Escherichia coli strain BL21（DE3） and C43（DE3） for inducible expression. The cytotoxicity of protein 2B was analyzed by comparing levels of expression in E. coli strain BL21（DE3） with that in C43（DE3） ,which is tolerant of toxic proteins. In result,2B gene was expressed only in E. coli strain C43（DE3） and the ex- pressed protein 2B inhibited the proliferation of both strains,indicating that the expressed protein 2B may have different levels of cytotoxicity to BL21（DE3） and C43（DE3）. In conclusion,the soluble 2B protein will provide the foundation for further study of 2B biological functions.