摘要
目的构建表达幽门螺杆菌(Hp)粘附素BabA重组蛋白的候选菌株并测定其粘附活性。方法用PCR方法从Hp染色体DNA上扩增粘附素babA2基因,将其定向插入表达载体pET-22b(+)中,并在BL21(DE3)大肠杆菌中表达,利用光镜计数法测定其粘附活性。结果DNA序列分析表明,所克隆的粘附素babA2基因序列与GeneBank公布的一致。在37 ℃诱导表达3 h后,粘附素BabA重组蛋白表达量占菌体总蛋白的34.8%,体外实验证实BabA参与了粘附过程。结论本研究获得了表达有生物活性的Hp粘附素BabA的克隆,为深入研究其相关功能奠定了良好基础。
Objective To construct a recombinant E.coli strain that highly expresses blood group Ag-binding adhesin (BabA) of Helicobacter pylori(Hp) and to assess the adherence activity of Hp BabA. Methods The gene fragment encoding BabA was amplified from Hp chromosomal DNA by PCR technique and inserted into prokaryotic expression vector pET-22b (+), which was then transformed into BL21 (DE3) E.coli strain for the expression of BabA recombinant protein. The adherence activity of Hp BabA obtained was assayed by counting under light microscope. Results DNA sequence analysis showed that the sequence of babA 2 DNA was in agreement with that published in GenBank. The BabA recombinant protein amounted to 34.8% of the total protein of the bacterium after IPTG induction for 3 h at 37 ℃, and BabA-mediated adherence was confirmed in vitro. Conclusion A clone expressing biologically active Hp BabA has been obtained, which may facilitate further study of the function of the adhesin.
出处
《第一军医大学学报》
CSCD
北大核心
2003年第4期293-295,309,共4页
Journal of First Military Medical University
基金
"863"计划专题(102-07-03-06)
国家自然科学基金(30170890
30270078)
军队"十五"医药卫生科研课题(OIMA-132)~~
