抗生素诱变的球形幽门螺杆菌定居毒力的研究

目的揭示抗生素诱变的球形幽门螺杆菌（Ｈｐ）与定居有关毒力的变异情况。方法采用亚抑菌浓度抗生素作用，使５株Ｈｐ发生球形变异，检测球形Ｈｐ的尿素酶活性及其对Ｈｅｐ２细胞（喉癌上皮细胞）的粘附性，并用ＰＣＲ法检测其尿素酶Ａ，尿素酶Ｂ及粘附素基因。结果球形Ｈｐ尿素酶活性降低，对Ｈｅｐ２细胞的粘附性降低，电镜下可见球形Ｈｐ侵入细胞内。球形Ｈｐ的４１１ｂｐ尿素酶Ａ，１１５ｂｐ尿素酶Ｂ及３７５ｂｐ粘附素基因的ＰＣＲ均阳性。结论抗生素诱变的球形Ｈｐ与定居相关的毒力减弱，但其有关毒力基因片段未缺失。

Study on the Colonizational virulence of coccoid Helicobacter Pylori induced by antibiotics

Objective To show the virulence related to the colonization of antibioticinduced coccoid Helicobacter pylori mutant. Methods Five strains of coccoid H. pylori, which were transformed from bacillary by exposure to antibiotics in subinhibitory concentrations, were examined by their activities of urease and their adherance to Hep2 cell, the gene variety of urease A, urease B and hpaA were analysed by PCR. Results Both activity of urease and adherance to Hep2 cell of coccoid H. pylori were decreased, and the invasion of coccoid H.pylori into hep2 cell could be seen under etectromicroscope, moreover, 411bp Ure A, 115bp UreB and 375bp hpaA in coccoid H.pylori were all shown to be positive as by PCR. Conclusion Virulence related to colonization in antibiotic induced coccoid H.pylori decreases, yet there is no deletion in virulencerelated gene fragments.