Valentin-Weigand P, Talay S R, Timmis K N, Chhatwal G S
Professorenstelle Mikrobiologie, TU Braunschweig, Gesellschaft für Biotechnologische Forschung (GBF), Germany.
Zentralbl Bakteriol. 1993 Apr;278(2-3):238-45. doi: 10.1016/s0934-8840(11)80841-8.
The role of streptococcal fibronectin-binding protein (Sfb protein) in the adherence of Streptococcus pyogenes to epithelial cells was analyzed by using a recombinant Sfb fusion protein which was constructed by fusion of the binding domain of Sfb protein to MS2 polymerase. Sfb fusion protein was overexpressed in Escherichia coli, purified from E. coli lysates by FPLC and analysed in binding experiments with 125I-labelled fibronectin and adherence studies with HEp2 epithelial cells. Lysates from E. coli expressing the fusion protein as well as purified Sfb protein competitively inhibited fibronectin binding and epithelial cell adherence of S. pyogenes, whereas streptococcal lipoteichoic acid (LTA), previously suggested to be the adhesin of S. pyogenes, had no effects. Southern blot analysis of chromosomal DNA from various streptococci revealed that the gene coding for the binding domain of Sfb protein was also present in other S. pyogenes strains. These results indicate that fibronectin-binding protein is the major adhesin of S. pyogenes.
通过使用重组Sfb融合蛋白分析化脓性链球菌纤连蛋白结合蛋白（Sfb蛋白）在化脓性链球菌黏附上皮细胞中的作用，该重组Sfb融合蛋白是通过将Sfb蛋白的结合结构域与MS2聚合酶融合构建而成。Sfb融合蛋白在大肠杆菌中过表达，通过快速蛋白质液相色谱法从大肠杆菌裂解物中纯化，并在与125I标记的纤连蛋白的结合实验以及与HEp2上皮细胞的黏附研究中进行分析。表达融合蛋白的大肠杆菌裂解物以及纯化的Sfb蛋白竞争性抑制化脓性链球菌的纤连蛋白结合和上皮细胞黏附，而先前认为是化脓性链球菌黏附素的链球菌脂磷壁酸（LTA）则没有作用。对各种链球菌染色体DNA的Southern印迹分析表明，编码Sfb蛋白结合结构域的基因也存在于其他化脓性链球菌菌株中。这些结果表明纤连蛋白结合蛋白是化脓性链球菌的主要黏附素。
