SALIVA PROTEINS AND BACTERIAL ADHESION TO ORAL SURFACES

这项建议的目的是了解分子机制。 参与共生菌和病原菌对牙齿的初始黏附 表面。对殖民的这一主要步骤的理解可以 为开发防止粘连的方法提供起点 病原体，并加强非致病物种的定居，因此 提供改善口腔健康的方法。细菌与细菌的黏附 牙齿似乎是由唾液、血清和 吸附在牙齿表面形成牙釉质的细菌 膜状的。在这笔赠款的前一段时间里，几种唾液蛋白 在它们的能力上表现出了显著的特异性 促进一些突出的口腔细菌与牙科矿物质的黏附。 本提案的目的是理解这些 分子水平上的粘附性相互作用。目标一.确定 一组新的人颌下腺发育能力的分子基础 舌下糖蛋白促进变形链球菌黏附的实验研究 JBP为羟基磷灰石(HA)。低聚糖的组成和结构 将确定纯化蛋白的组成和结构基础 对它们的活性和遗传多态性进行了研究。它们的吸附 HA及其与促进黏附活性的关系将是 量化的。目的II.阐明人唾液的分子特征 酸性富含脯氨酸的蛋白质(PRPS)，是它们能够 强烈促进粘性放线菌LY7、戈登放线菌和粘性放线菌的黏附 某些“变种”链球菌对HA。Pro的结构特点-- 杜松子酒羧基末端二肽，它似乎是中枢的 将对PRPS的活动进行调查。两个国家之间的差异 PrP基因产物及其更小分子的黏附促进活性 将对翻译后蛋白水解物进行研究。这个 结构不同的DB和PA PRPS的活动，以及一个新的 分离的多态PRP，将进行调查和比较。这些研究 的广泛多态性的意义。 PRP，他们不同寻常的翻译后分裂和在 相对基因表达，与细菌黏附相关。目标III.至 新鉴定的其他唾液蛋白的分离和鉴定 作为几种变形链球菌黏附的促进剂，戈登链球菌和 牙龈假单胞菌对HA的作用及其分子基础的研究 未研究的粘合反应。目的IV.分离和鉴定 表面分子介导变形链球菌JBP对APP的黏附，以及S. Gordonii到PRPS，吸附在HA上。纯净的唾液受体是 可提供数量，并将用于准备亲和柱 推定粘附素的提纯。分离的细菌细胞表面 分子将被评估为粘附素，通过它们与 受体，它们作为黏附抑制因子，并通过确定它们的 细菌细胞或其延伸部分上的位置。这些基因编码着 粘附素将被克隆和表达，为进一步的研究提供材料 研究，特别是研究粘附素-受体的相互作用 分子水平。

The objective of this proposal is to understand the molecular mechanisms involved in initial adhesion of commensal and pathogenic bacteria to tooth surfaces. An understanding of this primary step in colonization can provide a starting point for developing methods to prevent adhesion by pathogens and to enhance colonization by non-pathogenic species, so providing approaches to improving oral health. Adhesion of bacteria to teeth appears to be mediated by macromolecules from saliva, serum and bacteria that adsorb to tooth surfaces to form the acquired enamel pellicle. In the previous period of this grant, several salivary proteins were identified which showed remarkable specificity in their ability to promote adhesion of a number of prominent oral bacteria to dental mineral. The purpose of the aims of the present proposal is to understand these adhesive interactions at the molecular level. Aim I. To determine the molecular basis of the ability of a group of novel human submandibular- sublingual glycoproteins to promote the adhesion of Streptococcus mutans JBP to hydroxyapatite (HA). The composition and oligosaccharide structure of the purified proteins will be determined, and the structural basis of their activity and genetic polymorphism investigated. Their adsorption onto HA and its relationship to adhesion-promoting activity will be quantified. Aim II. To elucidate the molecular features of human salivary acidic proline-rich proteins (PRPs) which underlie their ability to strongly promote the adhesion of Actinomyces viscosus LY7, S. gordonii and certain "mutans" streptococci to HA. The structural features of the Pro- Gin carboxy-terminal dipeptide, which appears to be central to the activity of the PRPs, will be investigated. The differences in the adhesion-promoting activities of the PRP gene products and the smaller PRPs derived by post-translational proteolysis will be studied. The activities of the structurally different Db and Pa PRPs, and a newly isolated polymorphic PRP, will be investigated and compared. These studies will help clarify the significance of the extensive polymorphism of the PRPs, their unusual post-translational cleavages and differences in relative gene expression, related to bacterial adhesion. Aim III. To isolate and characterize additional salivary proteins recently identified as promoters of adhesion of several "mutans" streptococci, S. gordonii and P. gingivalis to HA, and to establish the molecular basis of these as yet uninvestigated adhesive reactions. Aim IV. To isolate and characterize the surface-molecules that mediate adhesion of S. mutans JBP to APPs, and S. gordonii to PRPs, adsorbed onto HA. The pure salivary receptors are available in quantity and will be used to prepare affinity columns for the purification of putative adhesins. Isolated bacterial cell surface molecules will be assessed as adhesins by their interaction with receptors, their acting as adhesion inhibitors, and by determining their location on the bacterial cells or their extensions. The genes coding for the adhesins will be cloned and expressed to provide material for further study, particularly for investigating adhesin-receptor interactions at the molecular level.