幽门螺杆菌细胞空泡毒素基因毒性片段的克隆与表达

目的：通过基因于程技术获得具有良好抗原性的重组细胞空泡毒素毒性亚单位蛋白。方法：利用PCR从幽门螺杆菌(Hp)空泡毒素基因中扩增毒性片段Ⅴ，克隆及序列分析后在大肠杆菌中高效表达，用免疫印迹法(Western blotting)检测其抗原性。结果：序列分析所得片段完整，与标准株AF361700比较有1．5％的bp及一个氨基酸发生变异。与文献报道的中国菌株相比有高度的同源性。SDS-PAGE显示表达产物相对分子量为27000，表达量为30％以上，Western blotting显示该蛋白可被HP全菌抗血清所识别。结论：基因重组Hp细胞空泡毒素毒性蛋白具有良好的抗原性，可用于制备Hp感染的诊断试剂与疫苗。

Cloning and expressing of vacA gene related segment with vacuolating activity of Helicobacter pylori

Objective:To obtain the antigen of recombinant vacuolating segment of Helicobacter pylori vacuolating cytotoxing by gene-engineering.Methods:The objective gene was cloned into PQE-30,sequenced and expressed using PCR and recombinant techniques.After expression,the antigenicity of recombinant protein was analyzed by Western blotting.Results:DNA sequence analysis identified that the sequence was integrated.Compared with standard strain AF361700,1.5% of the cloned gene was mutated,one amino acid radicle was changed.SDS-PAGE revealed the molecular weight of objective recombinant protein was 27 000 as it was predicted;the level of expression product was over 30%.Western blotting results showed the objective protein could be recognized by anti-serum against HP.Conclusion:This recombinant protein has perfect antigenicity,so it may be used as a protective antigen in preventing HP infection.