肝螺杆菌MCSTP的基因克隆及生物信息学分析

Cloning and bioinformatics analysis of recombinant methyl-accepting chemotaxis signal transduction protein of Helicobacter hepaticus

目的克隆肝螺杆菌(H.hepaticus)甲基基团接受趋化信号转导蛋白(MCSTP)全基因,并应用生物信息学方法对其进行分析。方法以肝螺杆菌全基因组作为模板,设计肝螺杆菌MCSTPc1977特异性引物,利用PCR方法扩增目的基因片段,连接至原核表达载体pET22b(+),从而构建原核表达质粒pET22b+/MCSTP并测序鉴定。应用生物信息学方法分析MCSTP基因的序列同源性及其结构特征。结果克隆的MCSTP基因经测序可知与GenBank公布的肝螺杆菌标准株ATCC51449序列一致性达99%,仅第1160bp处由A变为T。利用生物信息学方法进行分析可发现此基因与空肠弯曲杆菌、幽门螺杆菌具有非常低的相似性,表明其在微生物界中具有一定的特异性。结论成功构建pET22b+/MCSTP重组质粒,并通过生物信息学技术进行序列及结构分析,为进一步研究其生物学功能及致病机制提供了线索和依据。

Objective To clone the gene encoding methyl-accepting chemotaxis signal transduction protein （MCSTP） of Helicobacter hepaticus and analyze the gene structures using bioinfomatics methods. Methods With the specific primer of Helicobacter hepaticus MCSTP c 1977, MCSTP gene was amplified by PCR from the genomic DNA of Helicobacter hepaticus and ligated to the prokaryotic expression vector pET22b（＋）. After sequencing, the sequence homology and structural feature of MCSTP gene were analyzed by hioinformatics method. Results A 99% similarity was identified between MCSTP gene cloned and its counterpart in standard Helicobacter hepaticus strainATCCS1449genomeDNApublishedbyGenBank, withonlya replacement of A by T at 1160 bp. A low homology was found in the MCSTP genes between Helicobacter hepaticus, Campylobacter jejuni and Helicobacter pylori by bioinformatics analysis, suggesting the specificity of MCSTP gene in Helicobacter hepcaicus among the microbes. Conclusion The prokaryotic expression plasmid pET22b＋/MCSTP is constructed successfully, and the bioinformatics analysis provided evidences and clues for further study of the biological functions and pathogenic mechanism of MCSTP.