ROLE OF FIMBRIAE IN COLONIZATION BY BLACK-PIGMENTED BACTEROIDES

细菌类杆菌属的黑色素成员 (BPB)是口腔的殖民者，经常被发现 与口腔面部感染有关。口腔的定植 这些生物所造成的空洞必须涉及到它们与某些 环境组件，以防止被刷新 通过唾液或沟液的流动而消失。几乎所有的菌株 迄今被检查的BPB中携带菌毛的：蛋白质的聚合物 形成从细胞伸出的细丝的亚基(纤毛膜蛋白) 浮出水面。从其他证据中积累了大量证据 细菌种类以表明菌毛介导特定的 附着于多种表面，如上皮细胞或其他 细菌。我们建议通过确定 BPB菌毛的粘附性。由于BPB的表格A 相关物种的群体，出现了关于进化的问题 它们的菌毛之间的关系。因此，我们希望确定是否 BPB菌毛是祖先的亲缘关系。如果是这样，他们是否会执行 保守功能还是不同功能？如果它们没有血缘关系 但执行类似的功能，这是因为趋同进化吗？ 关联性将通过比较核苷酸来确定 克隆的菌毛蛋白编码基因的序列 亚单位。这些研究的完成将在 分子水平，对BPB使用的策略的理解 用于菌毛介导的粘连。信息将通过以下方式获得 通向这些策略的进化路径及其 在口腔定植中的潜在作用。

Black-pigmented members of the bacterial genus Bacteroides (BPB's) are colonists of the oral cavity, and are frequently found in association with oro-facial infections. Colonization of the oral cavity by these organisms must involve their adhesion to some component of the environment in order to resist being flushed away by saliva or the flow of crevicular fluid. Almost all strains of BPB's examined to date carry fimbriae: polymers of a protein subunit (fimbrilin) which form filaments that project from the cell surface. Considerable evidence has been accumulated from other bacterial species to show that fimbriae mediate specific adherence to a variety of surfaces such as epithelial cells or other bacteria. We proposed to test this hypothesis by determining the adhesive properties of BPB fimbriae. Since the BPB's form a group of related species, the question arises as to the evolutionary relationship of their fimbriae. Thus, we wish to determine if the BPB fimbriae are ancestrally related. If so, do they perform a conserved function or different functions? If they are unrelated but perform similar functions, is this due to convergent evolution? Relatedness will be determined by comparison of the nucleotide sequences of the cloned genes encoding the fimbrial protein subunits. Completion of these studies will provide, at the molecular level, an understanding of the strategies used by BPB's for fimbrial mediated adhesions. Information will be gained on the evolutionary pathways leading to these strategies and their potential roles in colonization of the oral cavity.