MOLECULAR BASIS OF THE ECOLOGY OF ORAL STREPTOCOCCI

口腔链球菌生态学的分子基础

• 批准号: 3219969
• 负责人: BURTON ROSAN
• 金额: $ 14.89万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-03-01 至 1987-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3219969
• 关键词: Streptococcus; Streptococcus mitis; Streptococcus mutans; Streptococcus salivarius; Streptococcus sanguis; bacterial genetics; cell adhesion; cell aggregation; dental caries; dental plaque; ecology; epithelium; gene expression; genetic strain; immunochemistry; macromolecule; membrane activity; molecular biology; oral bacteria; oral mucosa; periodontium disorder; saliva; surface antigens; teichoate

The exquisite specificity of the oral streptococci for different ecological niches within the oral cavity appears to be directly related to differences in their surfaces. Some of the differences may be directly observed at the ultrastructural level which indicates that the "fuzzy" coats (fimbriae) of Streptococcus salivarius which colonize epithelial cell surfaces are much longer than the fimbriae of S. sanguis, S. mitis or S. mutans which colonize tooth surfaces. Although the exact role of these fimbriae on surface structures in determining the particular ecological niche is not known, it is clear that these surfaces are involved in interactions with salivary pellicle resulting in plaque formation, saliva mediated bacterial aggregation, attachment to opithelial cells and interactions with other oral bacteria, e.g., corn cob formation. Thus, differences in the macromolecular composition of surfaces of the oral streptococci can be utilized as a model for the expression of differences in their ability to attach to different tissues. The attachment of bacteria to tissues appears to be the primary event in the initiation of many infectious diseases, including dental caries and periodontal disease. The objectives of the proposed studies are to develop a profile of the polysaccharide, teichoic acid and protein components of the surfaces of the oral streptococci using a combination of isotopic labeling techniques and analytical electro- phoretic methods. Using these profiles or "maps" as a guide, an investigation of the molecular basis of specificity for adherence will be undertaken employing strains of species which have different adherence properties, isogenic mutants and phenotypically altered cells. Extracts of these strains should give altered macromolecular profiles of their surfaces and thus provide the clues as to which molecules are associated with adherence. These molecules will be isolated, characterized chemically and immunochemically and studies of the cellular localization using immunohistochemistry will be undertaken. Finally, monospecific antiserum will be used to determine if adherence to oral tissues can be inhibited. These studies will provide a molecular taxonomy for the surfaces of oral streptococci which could be used as a basis for monitoring the effects of environment, antibody interaction, mutation and genetic transfer on the surfaces of oral streptococci.

口腔链球菌对不同生态的精致特异性 口腔内的生态位似乎与差异直接相关 在他们的表面。 一些差异可以直接观察到 超微结构水平表明“模糊”外套（菌毛） 定植于上皮细胞表面的唾液链球菌有很多 比 S. sanguis、S. mitis 或 S. mutans 的菌毛更长， 定殖于牙齿表面。 尽管这些菌毛的确切作用 决定特定生态位的表面结构不是 已知，很明显这些表面涉及与 唾液膜导致菌斑形成，唾液介导的细菌 聚集、附着于上皮细胞以及与其他细胞的相互作用 口腔细菌，例如玉米芯的形成。 因此，差异 口腔链球菌表面的大分子组成可以是 用作表达其能力差异的模型 附着于不同的组织。 细菌附着在组织上出现 是许多传染病发生的首要事件， 包括龋齿和牙周病。 该计划的目标 拟议的研究是开发多糖、磷壁酸的概况 使用口腔链球菌表面的酸和蛋白质成分 同位素标记技术和分析电分析技术的结合 电泳方法。 使用这些配置文件或“地图”作为指导， 对依从性特异性的分子基础的研究将是 使用具有不同依从性的物种菌株进行 特性、同基因突变体和表型改变的细胞。 摘录 这些菌株应该改变其表面的大分子轮廓 从而提供与哪些分子相关的线索 坚持。 这些分子将被分离、化学表征并 免疫化学和细胞定位研究 将进行免疫组织化学分析。 最后，单特异性抗血清 将用于确定是否可以抑制对口腔组织的粘附。 这些研究将为口腔表面提供分子分类学 链球菌可用作监测效果的基础 环境、抗体相互作用、突变和遗传转移 口腔链球菌的表面。