SALIVA PROTEINS AND BACTERIAL ADHESION TO ORAL SURFACES

唾液蛋白质和口腔表面的细菌粘附

• 批准号: 2130103
• 负责人: DONALD I HAY
• 金额: $ 21.19万
• 依托单位: ADA FORSYTH INSTITUTE, INC.
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-09-01 至 1997-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2130103
• 关键词: Actinomyces; Bacteroides gingivalis; SDS polyacrylamide gel electrophoresis; Streptococcus mutans; adhesin; affinity chromatography; cell adhesion; cell adhesion molecules; dipeptides; genetic polymorphism; hydroxyapatites; laboratory rabbit; molecular cloning; monoclonal antibody; oral bacteria; pellicle; posttranslational modifications; protein structure function; proteolysis; saliva; site directed mutagenesis; tooth surface; western blottings

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.

该提案的目的是了解分子机制 参与共生菌和致病菌对牙齿的初始粘附 表面。了解殖民化的这一主要步骤可以 为开发防止粘附的方法提供一个起点 病原体并增强非致病物种的定殖，因此 提供改善口腔健康的方法。细菌粘附 牙齿似乎是由唾液、血清和 吸附到牙齿表面形成后天牙釉质的细菌 薄膜。在本次资助的前一阶段，几种唾液蛋白 被鉴定出其能力表现出显着的特异性 促进许多重要的口腔细菌对牙科矿物质的粘附。 本提案的目的是为了了解这些 分子水平上的粘附相互作用。目标 I. 确定 一组新型人类下颌下能力的分子基础 舌下糖蛋白促进变形链球菌粘附 JBP 为羟基磷灰石 (HA)。组成及寡糖结构 将确定纯化蛋白质的结构基础 研究了它们的活性和遗传多态性。它们的吸附 HA 及其与粘附促进活性的关系将是 量化。目标二。阐明人类唾液的分子特征 酸性富含脯氨酸的蛋白质（PRP）是其能力的基础 强力促进 Actinomyces viscosus LY7、S. gordonii 和 某些“变形”链球菌与HA。 Pro的结构特点 杜松子酒羧基末端二肽，它似乎是 PRP 的活性将受到调查。差异在于 PRP 基因产物和更小的粘附促进活性 将研究翻译后蛋白水解产生的 PRP。这 结构不同的 Db 和 Pa PRP 的活性，以及​​新的 分离的多态性PRP，将被研究和比较。这些研究 将有助于阐明广泛多态性的意义 PRP，它们不寻常的翻译后裂解和差异 相对基因表达，与细菌粘附有关。目标三。到 分离和表征最近发现的其他唾液蛋白 作为几种“变形”链球菌、戈登链球菌和 P. gingivalis 到 HA，并建立这些的分子基础 未经研究的粘合反应。目标四。隔离并表征 介导变形链球菌 JBP 与 APP 粘附的表面分子，以及 S. mutans JBP 与 APP 的粘附。 gordonii 转化为 PRP，吸附到 HA 上。 纯唾液受体是 大量可用，将用于制备亲和柱 纯化假定的粘附素。分离的细菌细胞表面 分子将通过它们与的相互作用被评估为粘附素 受体，它们作为粘附抑制剂的作用，并通过确定它们 细菌细胞或其延伸物上的位置。编码基因 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-受体相互作用 分子水平。