VI型分泌系统2核心组分VgrG对禽致病性大肠杆菌致病性的影响  

Effects of type VI secretion system 2 core component VgrG on the pathogenicity of avian Escherichia coli

作　　者：刘新[1,2] 王少辉[2] 孟庆美[2] 韩先干[2] 许漩 杨登辉[2] 丁铲[2] 彭大新[1] 于圣青[2] 

机构地区：[1]扬州大学兽医学院,江苏扬州225009 [2]中国农业科学院上海兽医研究所,上海200241

出　　处：《微生物学通报》2016年第9期2106-2113,共8页Microbiology China

基　　金：国家自然科学基金项目(No.31572523;31370045);公益性农业(科研)专项项目(No.201303044);上海市科技兴农重点攻关项目(No.2015HNG1-9);中央级科研院所基本科研业务费项目(No.2015JB08)~~

摘　　要：【目的】构建禽致病性大肠杆菌(Avian pathogenic Escherichia coli,APEC)VI型分泌系统2(Type VI secretion system 2,T6SS2)结构基因vgrG缺失株,研究其对APEC生物学特性及致病性的影响。【方法】通过Red同源重组方法构建DE719菌株vgrG基因缺失株,并利用低拷贝质粒pSTV28构建互补株。比较分析野生株、缺失株与互补株的生长特性、运动性、生物被膜形成能力、黏附侵袭能力、动物致病力等差异。【结果】vgr G基因缺失不影响DE719的生长速度、运动能力及生物被膜形成能力。致病性试验表明缺失vgrG导致体内定殖能力及致病力显著下降,然而对DF-1细胞的黏附能力增强。【结论】T6SS2核心组分VgrG在APEC感染过程中发挥重要作用,为了解APEC的致病作用提供参考。[Objective] To determine the role of type VI secretion system 2（T6SS2） core component VgrG in avian pathogenic Escherichia coli（APEC）, we detected the biological characteristics and pathogenicity of APEC vgr G gene mutant strain. [Methods] We constructed the vgr G gene mutant strain and complementary strain of APEC DE719 by the Red recombination system and plasmid pSTV28. Then we analyzed the growth curve, motility, biofilm formation, adhesion and invasion capacity to DF-1 cells and virulence to duck of wild-type strain, mutant strain and complementary strain. [Results] The inactivation of vgr G gene did not affect the growth and motility, nor the biofilm formation of APEC. The vgr G gene mutant showed significantly decreased survival capacity and attenuated virulence in ducks. However, the adhesion capacity to DF-1 cells increased. [Conclusion] T6SS2 core component VgrG was involved in the process of APEC infection, which would help us to comprehensive understand the pathogenicity of APEC.

关 键 词：禽致病性大肠杆菌 vgrG基因 致病性 

分 类 号：S852.61[农业科学—基础兽医学]