鸡白痢沙门氏菌orgC基因缺失株的构建及生物被膜形成特性研究

Construction and Biofilm Formation Characteristics of orgC Gene Deletion Mutants of Salmonella Pullorum

为探索鸡白痢沙门氏菌Ⅲ型分泌系统效应蛋白OrgC在生物被膜形成中的作用,试验以鸡白痢沙门氏菌S9及其rpoS基因缺失株S9S为母本,利用Red同源重组系统构建orgC基因缺失株并利用原核表达载体构建回复株,测定其生物被膜形成能力和对鸡肝癌(Leghorn male hepatoma,LMH)细胞黏附入侵能力。结果显示:orgC基因缺失株生物被膜形成能力与野生株S9相比无显著变化,rpoS和orgC双基因缺失株生物被膜形成能力与rpoS基因缺失株S9S相比显著降低(P<0.05);orgC基因缺失株对LMH细胞入侵能力与野生株S9相比无显著变化,rpoS和orgC双基因缺失株对LMH细胞入侵能力与rpoS基因缺失株S9S相比显著降低(P<0.05)。研究表明,Ⅲ型分泌系统效应蛋白OrgC与鸡白痢沙门氏菌生物被膜形成及细胞入侵能力有关。

To investigate the role of type Ⅲ secretion system effector protein OrgC of Salmonella Pullorum on biofilm formation, Salmonella Pullorum strain S9 and its rpoS deletion strain S9S were selected as parent strains to construct orgC gene deletion mutants by Red recombinant system and complementary strains by using prokaryotic expression vector. Biofilm forming ability or adhesion and invasion ability to Leghorn male hepatoma(LMH) cells of the deletion mutants were determined. The results showed that biofilm forming ability of the orgC gene deletion mutant was similar as that of the wild type strain S9, and biofilm forming ability of the orgC and rpoS double genes deletion mutant was significantly lower than that of the rpoS deletion strain S9S(P<0.05). Invasion ability of orgC gene deletion mutant to LMH cells was similar as that of the wild type strain S9, and invasion ability of the orgC and rpoS double genes deletion mutant was significantly lower than that of the rpoS deletion strain S9S(P<0.05).It′s suggested that the effector protein OrgC of type Ⅲ secretion system would play roles in the biofilm formation and cell invasion of Salmonella Pullorum.