目的:构建HPV16L1基因的原核表达质粒,并优化其表达条件。方法:根据GeneBank中的HPV序列及pGEX-KG中的多克隆位点设计引物,以含有HPV全长基因片段重组质粒为模板,经PCR扩增出1 500 bp的DNA片段。将所得片段与pGEX-KG载体连接,转化JM109大肠杆菌,筛选阳性克隆。其扩增片段测序结果与原序列一致,表明原核表达载体pGEX-KG-HPV16L1已构建成功。提取pGEX-KG-HPV16L1质粒转化到BL21(DE3)表达菌株中,经IPTG诱导后收集菌体,进行SDS-PAGE,Western Blot鉴定。结果:在大肠杆菌中获得HPV16L1基因融合表达,融合蛋白的相对分子量为83kDa;表达的蛋白能与抗HPV16L1抗体发生特异性反应。结论:HPV16L1基因在大肠杆菌中获得高效表达,为HPV16L1疫苗的研制奠定了基础。
Objective: To construct the HPV16 L1 prokaryotic expression plasmid and to optimize its expression.Methods: A pair of primers was designed according to plasmid sequences of pGEX-KG and the HPV16L1 genes published by GeneBank.The DNA fragment of 1 500 bp was amplified by PCR from the HPV recombinant plasmid with HPV16L1 gene,then cloned into pGEX-KG and transformed into the host E.coli strain JM109.The pGEX-KG-HPV16L1 plasmid was taken and transformed into BL21(DE3) for expression.Induced by IPTG at 37℃,the expression product of HPV16L1 gene was identified by SDS-PAGE and Western blot.Results: HPV16L1 fusion protein was expressed successfully in the form of inclusion bodies.The molecular weight was 83 kD.Meanwhile,the optimum condition of HPV16L1 fusion protein expression was induced with 1.0 mmol·L-1 IPTG for 4 h.The fusion protein reacted specifically with antibodies against HPV16L1.Conclusion: The prokaryotic expression vector of HPV16L1 gene has been constructed and expressed in E.coli successfully.