密度感应系统luxS基因对鼠伤寒沙门菌生物学特性及毒力的影响  

Effects of quorum sensing system luxS gene on the biological characteristics and virulence of Salmonella typhimurium

作　　者：杨登辉[1,2] 汪洋[1,2] 王少辉[1] 刘新[1] 许漩 王栋[1] 韩先干[1] 丁铲[1] 程相朝[2] 于圣青[1] 

机构地区：[1]中国农业科学院上海兽医研究所,上海200241 [2]河南科技大学动物科技学院,河南洛阳471003

出　　处：《中国兽医科学》2016年第5期537-543,共7页Chinese Veterinary Science

基　　金：公益性行业(农业)科研专项(201403054)

摘　　要：通过构建鼠伤寒沙门菌luxS缺失株,研究其生物学特性及对Ⅵ型分泌系统(T6SS)的影响。利用Red同源重组系统构建鼠伤寒沙门菌luxS缺失株,比较野生株、luxS缺失株的生长特性、运动性、生物被膜、致病性等生物学特性的差异。利用荧光定量PCR、Western-blot对luxS基因缺失株T6SShcp1、hcp2和clpV基因转录水平和蛋白表达水平进行检测。结果显示,LuxS对鼠伤寒沙门菌生长速度、生物被膜形成能力及细胞黏附侵袭能力均无明显影响,但导致其运动性显著增强、致病力下降3.2倍,且不能合成自诱导分子2。在对数生长期和平台期,luxS基因均不影响T6SS核心组分Hcp1、Hcp2和ClpV的转录和表达。本研究表明,luxS基因缺失导致鼠伤寒沙门菌运动能力增强及毒力降低,但其不能影响T6SS核心组分的转录及表达。This study was performed to identify the role of luxS gene to the characterization and regulation of type VIsecretion system（T6SS）expression in S. typhimurium. We constructed the juxSmutant strain of S. typhimurium by the Red recombination system. Then we compared the growth curve,motility, biofilm formation,pathogenicity,transcriptional and expression levels of T6SS core components in mu- tant strain and wild-type strain. The results showed that growth eurve,biofilm formation,adhesion and invasion ability of mutant type were not significantly different to that of wild-type strain. However, inactivation of luxS gene resulted in enhanced motility,attenuated virulence in mice and failure in AI-2 synthesis. There were also no significant difference in transcriptional and expression levels of T6SS core components Hcpl,Hcp2,ClpV between the mutant strain and wild-type strain. These data indi- cated that luxS gene plays roles in motibility capability and virulence of S. typhimurium,but not in regulation of T6SS in S. typhimurium. The regulation of T6SS in S. typhimurium should be studied in thefuture.

关 键 词：沙门菌 Ⅵ型分泌系统 LUXS基因 调控 

分 类 号：S852.612[农业科学—基础兽医学]