目的:克隆结核分枝杆菌持续感染期抗原Rv1733c基因,构建其原核表达载体,并在大肠杆菌中进行表达和纯化。方法:采用聚合酶链反应(PCR)方法从结核分枝杆菌H37Rv基因组中扩增出Rv1733c基因片段,克隆入pMD18-T载体,序列测定正确后将其亚克隆入原核表达载体pPro-EXHTb,并在大肠杆菌DH5α中进行表达,表达蛋白经SDS-PAGE及Western-blot分析后,以Ni-NTA亲和层析纯化蛋白。结果:成功克隆了Rv1733c基因片段并构建了其原核表达载体pPro-EXHTb-1733c,转化E.ColiDH5α后能表达大小约30 KD的蛋白,Western-blot分析表明表达产物正确。通过亲和层析获得纯化蛋白。结论:成功构建结核分枝杆菌持续感染期抗原Rv1733c原核表达载体pPro-EXHTb-1733c,并获得纯化蛋白,为研究新型结核疫苗的靶抗原奠定了基础。
Objective: To clone the Rv1733c gene of Mycobacterium tuberculosis and express and purify the fusion protein.Methods:The Rv1733c gene was firstly amplified by PCR from genome of M.tuberculosis H37Rv strain and cloned into pMD18-T vector.After sequencing,the gene fragment was subcloned into the prokaryotic expression vector pPro-EXHTb and expressed in E.coli DH5a.The expressed protein was identified by SDS-PAGE analysis and Western-blot by using monoclonal antibody against 6×His,and the recombinant 6×His fused protein was purified by Ni-NTA purification system.Results:The gene of Rv1733c was cloned and expressed in E.coli DH5a.The relative molecular mass of this protein was consistent with the predicted.In Western-blot analysis,a specific binding band of this protein with 6×His mAb could be detected at the corresponding site with relative molecular mass of 30 kDa.Conclusion: The Rv1733c was successfully expressed and purified,which may be used as the target antigen for the novel vaccine against TB.