变形链球菌表面蛋白可变区(V+)基因克隆与表达

Cloning and Expression of Variable Domain (V+) Gene of Surface Protein of Streptococcus Mutans

目的 分离变形链球菌表面蛋白可变区 (V +)基因 ,构建V +表达克隆。方法 用PCR从sr基因中扩增目的基因片段V(+) ,亚克隆入中间载体 pCR2 1和表达载体 pET2 1a(+)。对重组体进行诱导表达并对表达产物进行SDS -PAGE和Westernblotting分析。 结果 PCR扩增产物为 1 16kb的DNA带 ,亚克隆入载体 ,获得重组克隆pCVf和重组表达克隆pSRVf,表达产物为 4 3kDa抗原 ,可以被抗Ⅰ /Ⅱ抗体特异性地识别。结论 本试验成功地构建了携带V +基因片段的表达克隆pSRVf。

Objective To isolate variable domain (V+) gene of the surface protein of streptococcus mutans and construct an expressive clone of V+ gene.Methods V+domain was amplified from gene sr by polymerase chain reaction (PCR) and subcloned into the plasmid vector pCR2.1 and the expressive plasmid vector pET21a(+).The recombinant was induced by IPTG to express target protein which was analysed by SDS-PAGE Western blotting.Results The specific product of PCR was about 1.16bp which was subcloned into vectors.The recombinant clone pCVf and the recombinant expressive clone pSRVf were obtained.pSRVf expressed specific protein with a molecular weight of 43kDa.This recombinant protein could be specifically recognized by anti Ⅰ/Ⅱ serum.Conclusion V+ domain of sr gene was cloned successfully.