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: 3222396
• 负责人: DONALD I HAY
• 金额: $ 19.23万
• 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/3222396
• 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.

本提案的目的是了解分子机制 参与牙本质和致病菌对牙齿的初始粘附 表面。对殖民化的这一主要步骤的理解可以 为开发防止粘连的方法提供了起点， 病原体和增强非致病性物种的定植， 提供改善口腔健康的方法。细菌粘附 牙齿似乎是由来自唾液，血清和 细菌吸附到牙齿表面形成后天的牙釉质 薄膜在本基金的前一阶段， 它们的特异性表现在 促进大量口腔细菌与牙齿矿物的粘附。 本提案的目的是了解这些 分子水平上的粘附相互作用。艾姆岛确定 一组新的人类下颌下- 舌下含糖蛋白促进变形链球菌粘附 JBP为羟基磷灰石（HA）。组成和寡糖结构 的纯化蛋白质将被确定，和的结构基础， 研究了它们的活性和遗传多态性。的吸附 HA及其与粘附促进活性的关系将是 量化。Aim II.目的：阐明人唾液腺癌基因的分子特征， 富含脯氨酸的酸性蛋白质（PRPs）， 对粘性放线菌LY 7、S.戈登和 某些“变异”链球菌对HA。Pro的结构特点 Gin羧基末端二肽，这似乎是核心的 将研究PRPs的活性。的差异 PRP基因产物的粘附促进活性和较小的 将研究翻译后蛋白水解产生的PRP。的 结构不同的Db和Pa PRP的活性，以及一种新的 分离的多态性PRP，将进行研究和比较。这些研究 将有助于澄清的意义，广泛的多态性的 PRPs，它们不寻常的翻译后裂解和 相关基因表达，与细菌粘附相关。Aim III.到 分离和表征最近鉴定的另外的唾液蛋白 作为几种变形链球菌的粘附促进剂，S.戈登和 P.牙龈透明质酸，并建立分子基础，这些尚未 未经研究的粘合剂反应。目标四。为了分离和表征 介导S.粘附的表面分子。mutans JBP到APP，以及S. gordonii的PRP，吸附到HA上。 纯唾液受体是 将用于制备亲和柱， 推定的粘附素的纯化。分离的细菌细胞表面 分子将通过它们与粘附素的相互作用被评估为粘附素。 受体，其作为粘附抑制剂，并通过确定其 在细菌细胞或其延伸上的位置。基因编码 粘附素将被克隆和表达，以提供用于进一步 研究，特别是用于研究粘附素受体相互作用， 分子水平。