Molecular Characterization of a Streptococcus gallolyticus Genomic Island Encoding a Pilus Involved in Endocarditis
Molecular Characterization of a Streptococcus gallolyticus Genomic Island Encoding a Pilus Involved in Endocarditis
复制标题
DOI：
10.1093/infdis/jir666
复制
发表时间：
2011-12-15
影响因子：
6.4
通讯作者：
Dramsi, Shaynoor
中科院分区：
文献类型：
--
作者：
Danne, Camille;Entenza, Jose M.;Dramsi, Shaynoor
方法：研究方法。对表达不同水平Pil1的鸡溶血性链球菌UCN34、Pil1(+)和Pil1(-)以及结构性表达Pil1的重组乳球菌进行了研究。针对可能的Pilin亚基Gallo2178和Gallo2179制备的多克隆抗体用于免疫印迹和免疫金电子显微镜观察。在大鼠心内膜炎模型上测试了Pil1的作用。我们发现Pil1基因(gallo2179-78-77)形成了一个操纵子，该操纵子在鸡溶血性链球菌不同菌株间存在差异表达。在鸡溶血链霉菌UCN34和表达乳酸乳杆菌的重组菌PIL1的表面都发现了短毛附着体。我们证明了Pil1菌毛参与了实验性心内膜炎的胶原结合、生物膜形成和毒力。本研究确定Pil1是鸡溶血性链球菌的第一个毒力因子。
Methods. S. gallolyticus UCN34, Pil1(+) and Pil1(-), expressing various levels of pil1, and recombinant Lactococcus lactis strains, constitutively expressing pil1, were studied. Polyclonal antibodies raised against the putative pilin subunits Gallo2178 and Gallo2179 were used in immunoblotting and immunogold electron microscopy. The role of pil1 was tested in a rat model of endocarditis.Results. We showed that the pil1 locus (gallo2179-78-77) forms an operon differentially expressed among S. gallolyticus strains. Short pilus appendages were identified both on the surface of S. gallolyticus UCN34 and recombinant L. lactis-expressing pil1. We demonstrated that Pil1 pilus is involved in binding to collagen, biofilm formation, and virulence in experimental endocarditis.Conclusions. This study identifies Pil1 as the first virulence factor characterized in S. gallolyticus.