幽门螺杆菌热休克蛋白A亚单位与大肠杆菌不耐热肠毒素B亚单位融合蛋白表达的研究

Expression of recombinant fusion protein of Escherichia coli heat-labile enterotoxin B subunit andHelicobacter pylori heat shock protein A subunit

目的 获得大肠杆菌不耐热肠毒素B亚单位 (LTB)与幽门螺杆菌保护性抗原热休克蛋白A亚单位 (HspA)的融合蛋白。方法 PCR扩增ltB和hspA基因 ,依次构建至表达载体pIM 1,转化大肠杆菌 ,SDS PAGE、免疫印迹分析目的蛋白表达情况。采用GM1 ELISA和D(+) 半乳糖亲和层析方法检测重组LTB HspA融合蛋白LTB组分与GM1 神经节苷脂结合活性。结果 重组LTB HspA融合蛋白表达量最高可达细菌总蛋白的 2 5 %。免疫印迹检测结果证实为重组LTB HspA融合蛋白。GM1ELISA和D(+) 半乳糖亲和层析方法检测结果证实重组LTB HspA融合蛋白具有与GM1 神经节苷脂结合的活性。结论 LTB HspA融合蛋白的表达研究 。

ObjectiveTo obtain fusion protein of E.coli heat labile enterotoxin B subunit and Helicobacter pylori heat shock protein A subunit.MethodsThe ltB and hspA genes were amplified by PCR. T hey were recombined in vitro with expression vector pIM 1 in turn and trans form ed into E.coli cells ,recombinant LTB HspA fusion protein was assayed by SD S PAGE and Western blot. The character of binding with ganglioside GM 1 was as sa yed with GM 1 ELISA and D(+) galactose affinity chromatography.Result s Recombinant E.coli strains expressing LTB HspA fusion protein wer e obtained. Recombinant protein amounted to 25% of the total bacterial protein. Recombinant fusion protein LTB HspA keeps the character of binding with LTB rec eptor ganglioside GM 1 from the results of GM 1 ELISA and process of purific atio n.Conclusions Expression of the fusion protein of E. coli L TB and H. pylori HspA in E. coli cells provide a basis to develop intram olecular adjuvant engineered vaccine against H. pylori.