幽门螺杆菌CagV蛋白的克隆表达及初步分析

目的构建幽门螺杆菌（Helicobacte rpylori）IV型分泌系统cagV（hp0530）基因的原核表达系统，表达并纯化CagV蛋白，初步分析其结构和抗原性，为进一步研究幽门螺杆菌的致病机制和治疗药物的筛选奠定基础。方法以H．Py—loriATCC700392株基因组为模板，采用聚合酶链反应（PCR）扩增获得目的片段，将其插入表达载体pET28a后转化大肠杆菌BL21（DE3），表达纯化后利用蛋白质印迹（Westernblot）分析CagV蛋白的抗原性。结果双酶切鉴定结果证实cagV基因重组表达载体构建成功；重组表达蛋白经飞行质谱鉴定为幽门螺杆菌CagV蛋白；Westernblot检测结果显示CagV蛋白具有特异抗原性。结论所克隆表达的CagV蛋白具有较好的抗原性，对后续的的H．pylori致病性和检测、分析研究有比较重要的意义。

Cloning and analysis of CagV in Helicobacter pylori

The aim is to clone, express and purify the CagV protein of Helicobacter pylori （H. pylori） type IV secre- tion system, and conduct preliminarily analysis on its structure and antigenicity for the further study of pathogenic mechanism and treatment of Helicobacter pylori. The cagV gene was amplified from H. pylori ATCC700392 genomic DNA and inserted into expression vector pET28a, and then transformed into E. colt BL21 （DE3） for the expression. The expression product was identified by SDS-PAGE and MALDI-TOF-MS and its antigenicity was tested by Western blot. Results indicated that the re- combinant protein was identified as Helicobacter pylori CagV protein by MALDI-TOF-MS. Western blot test result showed CagV protein had specific antigenicity for Helicobacter pylori. The CagV protein with good antigenicity has great significance for the further study of the pathogenicity and detection of the Helicobacter pylori.