VIBRATIONS, STRUCTURE AND DYNAMICS OF BIOMACROMOLECULES

描述：本研究的主要目标是表征 分子组织的双层，特别是，以提供 分子水平上的信息，有关的异质性的性质， 膜中脂质的横向分布。 这种异质性，只有 最近发现，在细胞膜上表现为松散的脂质镶嵌 域如果大小不同。 它的研究是重要的，因为它的作用， 脂质组成在调节 膜相关蛋白。 关于组织机构， 这些区域，特别是分子级尺寸的“微区域”。 的 在这项研究中使用的主要技术是红外和拉曼 光谱学，辅以量热法。 主要重点将放在 我国红外同位素法的发展和应用 模型膜中的微聚集。 这种技术测量微畴 最小的可能大小，1到100个分子，一个范围， 目前正在使用的其他技术。 目前我们 该方法只能应用于凝胶相，但将适用于 通过将其与快速冷冻方法相结合来实现流体相。 横向 膜中蛋白质周围的脂质组织将是 因为这类组织可能在流程中发挥重要作用 例如视觉传导。 其他研究将侧重于确定 混合脂双层中微区的结构和性质， 确定导致域形成的因素，并在可能的情况下， 测量所涉及的动力学。 的构象统计 在计算机模拟的双层链-这是越来越现实，现在 值得认真审查-将被批判性地分析和比较， 光谱测量 急需的振动光谱方法 用于测量双层中不饱和链的无序度， 沿着新的光谱方法来确定双层 结构

DESCRIPTION: The principal goal of this research is to characterize the molecular organization of the bilayer and, in particular, to provide molecule-level information concerning the nature of the heterogeneity in the lateral distribution of lipids in membranes. This heterogeneity, only recently revealed, is manifest in membranes as a loose mosaic of lipid domains if varying size. Its study is important because of the role that lipid composition plays in modulating the biological activity of membrane-associated proteins. Little is known about the organization of these domains, especially of molecular-level size "microdomains". The primary techniques to be used in this investigation are infrared and Raman spectroscopy, complemented by calorimetry. The main focus will be on the development and use of our infrared isotope method for measuring lateral microaggregation in model membranes. This technique measures microdomains of the smallest possible size, 1 to 100 molecules, a range that is inaccessible to the other techniques currently being used. At present our method can be applied only to the gel phase, but will be adapted for the fluid phase by combining it with fast-freeze methods. The lateral organization of the lipids surrounding proteins in a membrane will be investigated since such organization may play an important role in processes such as visual transduction. Other studies will focus on determining the structure and properties of microdomains in mixed lipid bilayers, on identifying the factors that lead to domain formation and, where possible, on measuring the kinetics involved. The conformational statistics of the chains in computer-modeled bilayers - which are ever more realistic and now worthy of serious scrutiny - will be critically analyzed and compared with spectroscopic measurements. Much needed vibrational spectroscopic methods for measuring disorder in the unsaturated chains in bilayers will be developed along with new spectroscopic approaches for determining bilayer structure.