VIBRATIONAL STUDIES OF LIPID STRUCTURE AND DYNAMICS

拉曼光谱已被广泛用于研究模型中的脂双层 和真实的生物膜，最近红外光谱学 成为一种同样可行的技术。 这些信息可以 从这些研究中得到的是多样的和独特的，多样的，因为 振动光谱对构象等因素的敏感性， 环境和移动性，并且由于快速的时间尺度而独特 与产生光谱的事件有关。 的对象 这个建议是为了解释光谱提供必要的基础 并将这些知识应用于特定模型系统的研究。 我们 本文将通过对模型烃链的研究来探讨这一问题 系统如正烷烃、羧酸和磷脂， 建立在我们早期工作的结果，建立定量的 振动光谱与结构和动力学之间的关系， 脂质胆固醇。 我们将着重于分离静态和动态效果。 静态效应包括链构象的影响， 其作为总体平均值和在脂质链中的特定位点将 是我们的主要目标之一。 另一个主要目标是， 动态影响，将通过分析来评估链的流动性， C-H伸缩带形状，从而提供了一种全新的 关于双分子层的信息。 一种新的“平均链”分析方法 无序烃链的振动在脂类光谱中的应用 将被开发。 我们识别不同类型的本地化 将利用链中的构象缺陷来建立关系 在双层的相和相关联的 构象紊乱。 链研究技术的应用 构象和流动性将被用于研究压力反转， 麻醉剂诱导的模型膜系统紊乱。

Raman spectroscopy has been much used to study the lipid bilayer in model and real biological membranes, and recently infrared spectroscopy has emerged as an equally viable technique. The kinds of information that can be derived from these studies are varied and unique, varied because of the sensitivity of vibrational spectra to factors such as conformation, environment, and mobility, and unique because of the fast time scale associated with the events that give rise to the spectra. The object of this proposal is to provide the needed groundwork for interpreting spectra and to apply this knowledge to the study of specific model systems. We will approach this problem through the study of model hydrocarbon chain systems such as n-alkanes, carboxylic acids, and phospholipids and will build on the results of our earlier work in establishing quantitative relations between vibrational spectra and the structure and dynamics of the lipid bilyer. We will focus on separating static and dynamic effects. Static effects include those of chain conformation, the determination of which as an overall average and at specific sites in the lipid chain will be one of our principal aims. Another principal aim, associated with dynamic effects, will be to evaluate chain mobility through an analysis of C-H stretching band shapes and thus provide a completely new kind of information about the bilayer. A new "average-chain" approach to analyzing the vibrations of disordered hydrocarbon chains applicable to lipid spectra will be developed. Our ability to identify different types of localized conformational defects in chains will be utilized to establish relations between the phase of the bilayer and the nature of the associated conformational disorder. Application of the techniques for studying chain conformation and mobility will be made to the study of pressure reversal of anesthetic induced disorder in model membrane systems.