幽门螺杆菌vacA基因变异性研究

目的：探索幽门螺杆菌（Helicobacter pylori,简称Hp)vacA基因（vacuolating cytotoxin gene A)的变异性及其与产生空泡毒素活性的关系。方法：用自行设计的两两配对的4条引物对17株Hp的vacA基因进行PCR扩增。结果：每株细菌均可扩增出包括vacA基因不同区域的4条产物，但每种产物在不同菌株间长度有差异；对产毒株与非产毒株的扩增产物长度比较，未发现与产毒有关的区域。结论：Hp vacA基因的变异性相当大，变异部位不仅仅局限于某一区域，沿不能确定与产毒有关的基因区域。推测Hp表达VacA活性与否可能与分泌的量有关。

Study on divergence of vacA gene among Helicobacter pylori

Objective In order to find the divergence of vacA (vacuolating cytotoxin gene A) among H. pylori strains and explore the relationship between divergence of vacA and of VacA (Vacuolating cytotoxin A). Methods vacA gene of 17 H. pylori strains were amplified by PCR using 4 primers which were designed in our laboratory and matching each other. Results Four kinds of amplifications including different regions of vacA gene were obtained for every H. pylori strains. But the length of amplifications of 17 strains for each pair of primer were variable and the region corresponding to VacA was not found through comparing the length of amplification among tox H. pylori and tox - H. pylori . Conclusions There is very significant divergence of vacA gene among H. pylori strains and the region of vacA gene which has relationship with VacA was to be determined. It is assumed that vacuolating activity is positively related to quantity of VacA secreted.