GENETICS OF VIRULENCE DETERMINANTS OF BLACK-PIGMENTED BACTEROIDES

类杆菌属的黑色成员 (BPB的）是口腔的殖民者，并且经常被发现 与口面部感染有关。 口腔定植 这些生物体的空腔必须涉及它们对某些 环境的组成部分，以抵抗被冲洗 通过唾液或龈沟液的流动而离开。 几乎所有菌株 到目前为止检查的BPB携带菌毛：蛋白质的聚合物 形成从细胞突出的细丝的亚单位（菌毛蛋白） 面 从其他方面积累了大量证据， 细菌物种，以表明菌毛介导特异性 粘附于各种表面，例如上皮细胞或其它 细菌 我们建议通过确定 BPB菌毛的粘附性能。 由于BPB的表格A 一群相关的物种，问题出现了， 它们的菌毛的关系。 因此，我们希望确定， BPB菌毛有祖先关系。 如果是，他们是否执行 是保守的功能还是不同的功能？ 如果他们没有关系 但功能相似，这是趋同进化的结果吗 相关性将通过比较核苷酸 编码菌毛蛋白的克隆基因的序列 亚单位。 这些研究的完成将提供， 分子水平，了解BPB使用的策略 用于菌毛介导的粘连。 将获得以下信息： 导致这些策略的进化途径及其 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.