乙脑病毒包膜蛋白可溶性表达及纯化

Expression and purification of the soluble envelope protein of Japanese encephalitis virus

目的：通过原核表达载体对乙脑病毒包膜蛋白进行可溶性表达和纯化。方法筛选不同的表达载体、宿主菌株、表达条件，以获得可溶性的目的蛋白表达。采用镍柱和凝胶过滤层析对表达蛋白进行纯化。结果对不同的载体、菌株、表达条件筛选后，最终发现PBCX载体与乙脑病毒包膜蛋白E406基因连接后的质粒，在低温诱导后获得可溶性E蛋白表达，且表达量较高。表达量占可溶性蛋白总量的23％。通过镍柱和凝胶过滤层析纯化后，目的蛋白纯度较高，达85％，满足试验需求。结论本研究获得了可溶性表达的乙脑病毒E蛋白，方法简单高效，为深入研究该蛋白生物学特性和功能，解析乙脑病毒的致病机制、乙脑减毒活疫苗毒株的减毒机制及其质量控制，乙脑诊断试剂开发，奠定了技术基础。

Objective To express and purify the envelope （ E） protein of Japanese encephalitis virus （JEV） in soluble form.Methods Various prokaryotic expression vectors , host strains and induction conditions including time and temperatures were screened to obtain an optimum prokaryotic expression system for JEV E protein in soluble form .The expressed protein was purified by using nickel column chromatography and gel filtration chromatography .Results The soluble JEV E protein , accounting for 23% of the totally bacteria soluble protein was effectively expressed by using the recombinant plasmid PBCX -E406 at low tem-perature.The purity of the expressed protein reached up to 85%after the purification by using nickel column and gel filtration chromatography .Conclusion Soluble JEV E protein was successfully expressed and purified in a simple and efficient way .It would provide a useful tool for further investigation on JEV infection , attenuation mechanism of JE live vaccine strain SA 14-14-2 and the quality control of JE vaccine .It can also be used for the development of diagnosis assay for JEV .