Kopp P A, Schmitt M, Wellensiek H J, Blobel H
Institut für Bakteriologie und Immunologie, Justus-Liebig-Universität Giessen, Germany.
Infect Immun. 1995 Oct;63(10):3804-8. doi: 10.1128/iai.63.10.3804-3808.1995.
Adherence of bacteria to host cell membranes is one of the initial steps of microbial pathogenicity. Numerous studies have suggested that fibronectin promotes this interaction in some bacterial species. In this study, we have examined the ability of Borrelia garinii to bind fibronectin. The binding of fibronectin to the spirochete was specific and saturable. Scatchard plot analysis of the binding data revealed two types of ligands on the spirochetal surface, one with high affinity and one with low affinity for fibronectin. The fibronectin-binding sites were solubilized from the surface of B. garinii N34 by lysozyme treatment. Fast protein liquid chromatography (FPLC) purification of the solubilized binding sites resulted in one band with a high fibronectin-binding activity and a molecular weight of ca. 147,000. FPLC-purified binding sites, fibronectin, and antibodies to fibronectin inhibited the adherence of the spirochete to epithelial cells competitively. These data provide strong support for the hypothesis that fibronectin-binding sites on the surface of B. garinii are involved in the adherence of the spirochete to their respective host cells.
细菌对宿主细胞膜的黏附是微生物致病性的初始步骤之一。众多研究表明，纤连蛋白在某些细菌种类中促进这种相互作用。在本研究中，我们检测了莱姆病疏螺旋体结合纤连蛋白的能力。纤连蛋白与螺旋体的结合是特异性且可饱和的。对结合数据进行Scatchard作图分析显示，螺旋体表面存在两种类型的配体，一种对纤连蛋白具有高亲和力，另一种具有低亲和力。通过溶菌酶处理从莱姆病疏螺旋体N34表面溶解纤连蛋白结合位点。对溶解的结合位点进行快速蛋白质液相色谱（FPLC）纯化，得到一条具有高纤连蛋白结合活性且分子量约为147,000的条带。FPLC纯化的结合位点、纤连蛋白以及抗纤连蛋白抗体竞争性抑制螺旋体对上皮细胞的黏附。这些数据为如下假说提供了有力支持，即莱姆病疏螺旋体表面的纤连蛋白结合位点参与螺旋体对其各自宿主细胞的黏附。
