CONFORMATION OF DENTAL SALIVARY MOLECULES

该项目的长期目标是定义之间的关系 唾液大分子的构象及其生物学 功能。 最终，这些信息将用于开发合成 唾液用于唾液功能障碍患者。 初步研究 将重点关注以下两种腮腺唾液大分子：（1） “statherin”和(2)富含脯氨酸的糖蛋白“PRG”。 生物的 statherin 和 PRG 的功能包括调节 唾液和牙齿表面之间的钙-磷酸盐平衡，而 PRG 还参与咀嚼润滑，获得性的形成 牙釉质薄膜和细菌从口腔中清除。 的 研究方法将是圆二色性（CD）和二维 H1-核磁共振 (n.m.r.) 光谱。 这个特别的 方法学和唾液大分子的结合非常适合 彼此因为：（1）存在这些分子的一级序列数据并且 (2)它们足够小，可以进行严格的构象分析。 的 具体的研究方法将首先利用确定的合成多肽 半经验预测的二级结构域的类似物 计算。 一旦二级结构的存在被建立 使用 CD 光谱法，n.m.r.分析将开始。 使用核磁共振 方法，将获得大约一半的肽键角。 的 剩余的肽键角度将通过计算机分析来指定。 这个 将对每个二级结构域重复该过程，直到 整个二级构象已经被绘制出来。 下一步为 富酪蛋白将从合成多肽模型转向 天然的、完整的分子。 Statherin 将通过核磁共振检查。光谱学 和指定的三级结构。 认识3维 富酪蛋白和选定的钙结合功能域的结构 在 PRG 中，随后将进行钙滴定，并且 将阐明构象。 根据这些结果，计算机分析 将用于预测是否可以建立更有效的功能域 开发的。 钙结合和/或的改进的合成类似物 statherin 和 PRG 的润滑功能域分别将 然后进行准备和测试以增强生物活性。

The long range goal of this project is to define the relationships between the conformation of salivary macromolecules and their biological functions. Ultimately, this information will be used to develop synthetic saliva for use in patients with salivary dysfunctions. Initial studies will focus on the following two parotid salivary macromolecules: (1) "statherin" and (2) the proline-rich glycoprotein, "PRG". The biological functions of statherin and PRG include the regulation of the calcium-phosphate equilibrium between saliva and the tooth's surface, while PRG also takes part in masticatory lubrication, the formation of acquired dental enamel pellicle and bacterial clearance from the oral cavity. The methods of study will be circular dichroism (CD) and 2-dimensional H1-nuclear magnetic resonance (n.m.r.) spectroscopies. This particular combination of methodologies and salivary macromolecules are well suited to each other since: (1) primary sequence data exists for these molecules and (2) they are small enough to undergo rigorous conformational analyses. The specific methods of study will first utilize defined synthetic polypeptide analogs of secondary structural domains as predicted by semi-empirical calculations. Once the presence of that secondary structure is established with CD spectroscopy, the n.m.r. analysis will begin. Using n.m.r. methods, roughly half of the peptide bond angles will be obtained. The remaining peptide bond angles will be specified by computer analysis. This procedure will be repeated for each secondary structural domain until the entire secondary conformation has been mapped out. The next step for statherin will be to proceed from the synthetic polypeptide models to the native, intact molecule. Statherin will be examined by n.m.r. spectroscopy and the tertiary structure specified. Knowing the 3-dimensional architecture of statherin and selected calcium-binding functional domains in PRG, calcium titrations will then be performed and changes in conformation will be elucidated. Based on these results, computer analysis will be used to predict if more effective functional domains can be developed. The improved synthetic analogs of the calcium-binding and/or lubricatory functional domains for statherin and PRG, respectively, will then be prepared and tested for enhanced biological activity.