CONFORMATION OF DENTALLY RELEVANT SALIVARY MOLECULES

这个项目的长期目标是定义 唾液分子的构象和它们的 生物功能。 最初的研究将集中在两种分子上 在腮腺唾液中发现：（A）富含酪氨酸的磷蛋白， （B）富含脯氨酸的糖蛋白“PRG”。 的 对这项研究最重要的生物学功能 关于statherin是调节磷酸钙 唾液和牙齿表面之间的平衡。 关于 PRG，与本项目相关的生物学功能是 从口腔和咀嚼肌中清除细菌 润滑 基于计算机的方法用于 结构分析是核磁共振（NMR）， 圆二色性（CD）、紫外/可见光（UV/维斯）和 荧光光谱 基于理论的程序 对于构象的阐明，将包括对 通过能量最小化产生的定量结果， 计算机生成的分子结构的目视检查 建模 将这些特定方法应用于 上述唾液分子已经提供了 详细介绍了N- PRG的糖基化位点，并有望进一步阐明 天然Statherin和其它的三维结构 PRG中的功能域。 简单地说，这些程序 结构分析包括首先检查光学（例如金属 离子、盐、pH、温度、离液剂、化学探针， 其它大分子等）。 这些信息提供了以下数据： 的主体二级和三级结构， 蛋白质/肽。 然后使用NMR光谱来阐明 在原子水平上的构象， 从计算机建模程序中导出。 选择 然后测试天然分子的片段的生物活性， 活动和结构分析。 以这种方式， 功能结构域仍然保留生物活性的 可以分离母体分子。 一旦完成， 制备类似物并测试其增强的生物活性 在体外分析系统中。 一个这样的功能 目前正在研究的结构域是环状新糖肽 PRG的N-糖基化位点的类似物。 最终，这些 类似物将被用作清除病原性 从口腔和病人的合成唾液中的细菌 唾液分泌障碍

The long range goal of this project is to define the relationships between the conformation of salivary molecules and their biological functions. Initial studies will focus on two molecules found in parotid saliva: (A) the tyrosine-rich phosphoprotein, "statherin" and (B) the proline-rich glycoprotein, "PRG". The biological function of greatest importance to this study concerning statherin is the regulation of the calcium-phosphate equilibrium between saliva and the tooth's surface. Regarding PRG, the biologically relevant functions to this project are bacterial clearance from the oral cavity and masticatory lubrication. The empirically-based methods to be used for structural analyses are nuclear magnetic resonance (NMR), circular dichroism (CD), ultraviolet/visible (UV/VIS) and fluorescence spectroscopies. The theoretically-based procedures for elucidation of conformation will include both evaluation of the quantitative results produced through energy minimization and visual inspection of molecular structures generated by computer modeling. The application of these particular methodologies to the aforementioned salivary molecules has already provided detailed information concerning the conformation of the N- glycosylation sites of PRG and promises to further elucidate the three-dimensional structures of native statherin and other functional domains in PRG. Briefly, the procedure for these structural analyses involves first examining the optical (e.g. metal ions, salt, pH, temperature, chaotropic agents, chemical probes, other macromolecules, etc). This information provides data on the bulk secondary and tertiary structures of the proteins/peptides. NMR spectroscopy is then used to elucidate the conformation at the atomic level with further refinements derived from the computer modeling programs. Selected fragments of the native molecules are then tested for biological activity and structurally analyzed. In this way the minimum functional domain still retaining the biological activities of the parent molecule can be isolated. Once this is accomplished, analogs are prepared and tested for enhanced biological activities in the in vitro assay systems. One such proposed functional domain currently being investigated is a cyclic neoglycopeptide analog of the N-glycosylation sites of PRG. Ultimately, these analogs will be used as an aid for the clearance of pathogenic bacteria from the oral cavity and in synthetic salivas for patients with salivary dysfunction.