tolB和tolR基因缺失对鼠伤寒沙门菌生物学功能的影响  

Effect of tolB and tolR gene deletions on biological functions of Salmonella Typhimurium

作　　者：费霞 田一辰 黄山 周国栋 李权 石火英[1,2] FEI Xia;TIAN Yi-chen;HUANG Shan;ZHOU Guo-dong;LI Quan;SHI Huo-ying(College of Veterinary Medicine,Yangzhou University,Yangzhou 225009,China;Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses,Yangzhou 225009,China)

机构地区：[1]扬州大学兽医学院,江苏扬州225009 [2]江苏省动物重要疫病与人兽共患病防控协同创新中心,江苏扬州225009

出　　处：《中国兽医科学》2022年第11期1422-1429,共8页Chinese Veterinary Science

基　　金：国家自然科学基金青年基金项目(320023010);中国博士后科学基金项目(2019M661953);国家自然科学基面上项目(31672526);江苏省高校优势学科建设工程资助项目(PAPD)。

摘　　要：Tol-Pal系统是一种由TolQ、TolR、TolA、TolB和Pal五种包膜蛋白组成的多蛋白复合体,在维持革兰氏阴性菌外膜完整性方面发挥关键作用。这些蛋白质首先在大肠杆菌中被发现,随后在很多其他细菌属中被鉴定到,但Tol-Pal系统在鼠伤寒沙门菌(Salm onella Typhimurium)中的作用尚不十分清楚。本研究评估了Tol-Pal系统中的TolB和TolR蛋白在鼠伤寒沙门菌χ3761表型和生物学中的作用。结果显示,tol B和tolR缺失株显著降低了χ3761的运动能力,tolB和tolR缺失株菌体呈现球形和长链状,此外还发现菌体表面存在鞭毛缺失和囊泡凸起的微观变化,证实tolB和tolR的缺失对细胞壁造成了严重的破坏。结果表明,tolB和tolR缺失株均显著降低了鼠伤寒沙门菌在脱氧胆酸钠作用下的存活率,并对万古霉素表现出高度敏感性,这可能是由于包膜完整性受到破坏所致。进一步的研究表明,tolB和tolR基因均参与外膜囊泡(OMVs)的产生。综上所述,这项研究扩展了我们对鼠伤寒沙门菌Tol-Pal系统生物学功能的认识。The Tol-Pal system,consisting of five envelope proteins Tol Q,Tol R,Tol A,Tol B,and Pal,is necessary for maintaining outer membrane integrity.These proteins were first described in E.coli,and subsequently been identified in many other bacterial genera.However,the role of the Tol-Pal system in Salmonella Typhimurium is still not well understood.Here,we reported the role of Tol B and Tol R proteins in the phenotype and biology of Salmonella Typhimuriumχ3761.We found that the tol B and tol R mutants significantly reduced the motility ability.Moreover,this study revealed that deletion of tol B and tol R showed an altered morphology with flagella defect,long chains,spherical forms,and formed vesicles at the cell surface,confirming that the tol B and tol R mutants were severely damaged in their outer membrane integrity.We confirmed that the tol B and tol R mutants significantly decreased Salmonella Typhimurium survival when exposed to sodium deoxycholate and exhibited a high sensitivity to vancomycin,which may be explained by the disruption of envelope integrity.Further investigation showed that tol B and tol R are involved in OMVs production.Collectively,this study expanded our understanding of the biological role of the Salmonella Typhimurium Tol-Pal system.

关 键 词：Tol-Pal系统 tolB tolR 鼠伤寒沙门菌 外膜完整性 OMVs 

分 类 号：S852.612[农业科学—基础兽医学]