FORCES GOVERNING PROTEIN RECOGNITION DYNAMICS

控制蛋白质识别动力学的力量

• 批准号: 2189792
• 负责人: Deborah E Leckband
• 金额: $ 10.37万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-30 至 1995-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2189792
• 关键词: acidity /alkalinity; antigen antibody reaction; avidin; chemical association; computer program /software; cytochrome b; cytochrome c; electrical potential; fluorescence microscopy; fluorescent dye /probe; gangliosides; glycosylation; hydropathy; immunoglobulin G; intermolecular interaction; ionic bond; ionic strengths; ligands; molecular dynamics; molecular film; molecular polarity; monoclonal antibody; protein structure function; stereochemistry; structural biology

The aim of this research is to directly measure the inter molecular forces governing the dynamics of protein recognition and associations with other proteins, small molecules, and membrane bound receptors. To this end, we will use a surface forces apparatus to directly measure the molecular forces between uniformly oriented protein monolayers and a second protein or ligand monolayer. We will focus on direct measurements of three main aspects of protein structure that impact protein recognition and function: namely, the l) the protein electrostatic surface potentials, 2) the long- ranged inter molecular forces that guide inter molecular docking and enhance kinetic association rates, and 3) the molecular basis of glycosylation or membrane carbohydrate perturbations to protein recognition of macromolecules of membrane-bound receptors. In the first stage of this work, we will directly measure the electrostatic surface potentials of two distinct surface regions of two rat liver cyt b5 variants, the binding surface of cyt c, and the binding surfaces of the Fab' fragments of two monoclonal antifluorescyl IgG idiotypes. We will compare our results with theoretically determined electrostatic potential fields corresponding to the identical protein surface regions. in the second stage, we will elucidate all constituent non contact inter molecular forces such as electrostatic and van der Waals forces that determine protein-ligand association rates. We will also establish the significance of surface charge polarity in reorienting misaligned reactive pairs. We will determine the effects of both active site and external surface mutations on the long ranged inter molecular recognition forces. In the third stage, we will extend our studies beyond the quaternary protein structure to examine the effects of protein glycosylation and membrane glycolipids on both specific and nonspecific protein interactions. We will determine the molecular effects of avidin glycosylation on interfacial binding. We will also determine the impact of gangliosides on receptor-mediated inter membrane adhesion as a function of the ganglioside identity (GM1 and GT3) and of its surface density. Knowledge of the molecular forces governing protein recognition is essential to our understanding of the fundamental basis of protein function. Quantitative determinations of the forces dictating protein behavior will facilitate the a priori predictions of protein function and behavior as well as the rational engineering of proteins with enhanced or finely tailored activities. Furthermore, such measurements will lead to the refinement of existing theoretical models.

这项研究的目的是直接测量分子间力 管理蛋白质识别的动态以及与其他 蛋白质，小分子和膜结合受体。为此，我们 将使用表面力设备直接测量分子 均匀定向的蛋白质单层和第二个蛋白质之间的力 或配体单层。我们将专注于三个主要的直接测量 影响蛋白质识别和功能的蛋白质结构的各个方面： 即，l）蛋白质静电表面电位，2）长期 引导分子间对接和 提高动力学缔合率，3） 糖基化或膜碳水化合物扰动蛋白 识别膜结合受体的大分子。在第一个 这项工作的阶段，我们将直接测量静电表面 两个大鼠肝Cyt B5的两个不同表面区域的电势 变体，Cyt C的结合表面和结合表面 两种单克隆抗氟乙酰菌IgG白痴的Fab'片段。我们将 将我们的结果与理论确定的静电电势进行比较 对应于相同蛋白质表面区域的场。在 第二阶段，我们将阐明所有成分非接触间 分子力，例如静电和范德华力， 确定蛋白质 - 配体关联速率。我们还将建立 表面电荷极性在重新对准反应性的重新对准的重要性 成对。我们将确定活动站点和外部的影响 长期范围的分子间识别力上的表面突变。 在第三阶段，我们将研究我们的研究超越第四纪 蛋白质结构检查蛋白质糖基化的作用和 特异性和非特异性蛋白上的膜糖胶质 互动。我们将确定抗原素的分子效应 对界面结合的糖基化。 我们还将确定影响 受体介导的膜间粘附的神经节剂作为功能 神经节苷脂的身份（GM1和GT3）及其表面密度。 了解蛋白质识别的分子力的知识是 我们对蛋白质基本基础的理解至关重要 功能。决定蛋白质的力的定量确定 行为将促进蛋白质功能的先验预测和 行为以及具有增强或增强的蛋白质的合理工程 量身定制的活动。此外，这样的测量将导致 现有理论模型的完善。