摘要
目的利用Red同源重组技术构建肠出血性大肠杆菌(EHEC)O157∶H7外膜蛋白A(ompA)基因敲除菌株,研究敲除菌株的黏附能力变化,阐明OmpA在细菌黏附以及致病中的作用。方法利用Red同源重组技术对EHEC O157∶H7 ompA基因进行敲除,同时构建EHEC O157:H7 ompA回复突变菌株,最后通过细胞试验对EHEC O157∶H7野生型菌株、敲除菌株及回复突变菌株的黏附能力进行比较。结果成功构建了EHEC O157:H7 ompA基因敲除菌株及其回复突变菌株。细胞试验结果表明,与野生型菌株相比,敲除菌株的黏附能力明显下降,而将ompA基因进行回复突变后其黏附能力又得到回复。结论 OmpA在EHEC O157∶H7黏附HeLa细胞过程中发挥重要作用,ompA基因敲除菌株的获得为进一步研究其功能提供了帮助。
In this study,gene encoding outer membrane protein A(ompA) of enterohaemorrhagic Escherichia coli(EHEC) O157:H7 was knocked out(ompA-) using λ red homologous recombination system.To clarify the roles of OmpA in cell adhesion and pathogenesis,ompA-EHEC O157:H7 was then complemented with a plasmid containing the ompA gene and its promoter(ompA+).Meanwhile,the ability of ompA+ EHEC O157∶H7 and ompA-EHEC O157∶H7 strains to attach to HeLa cells were compared with that of wild type EHEC O157∶H7 through cell adhesion assay.Results showed that the cell adhesion ability of ompA-EHEC O157:H7 strain decreased significantly,when compared with that of wild type EHEC O157:H7 and ompA+ EHEC O157:H7.These data demonstrated that the OmpA of EHEC O157:H7 may play an important role in HeLa cell adhesion.In addition,ompA-EHEC O157∶H7 strain obtained in this study would provide a useful tool for the further study of EHEC O157∶H7 pathogenesis.
出处
《免疫学杂志》
CAS
CSCD
北大核心
2012年第5期420-423,共4页
Immunological Journal
基金
国家重大新药创制专项课题(2008ZXJ09014-007)