NMR STUDIES OF BIOLOGICAL MEMBRANES

固态核磁共振光谱和共振拉曼 光谱学将被用作研究的非微扰手段， 蛋白质和多肽的结构、动力学和功能机制 参与膜运输。 特别是，我们计划研究 盐杆菌质膜的紫色膜碎片 halobium，其中包含一个单一的蛋白质，执行光驱动的质子 运输和模型膜含有恩镰孢菌素离子载体， 促进被动阳离子运输。 样品将进行同位素富集 在特定的位置，以增强感兴趣的NMR信号，抑制干扰 NMR信号，并诱导共振拉曼中的信息位移 江西篇章 在紫膜的情况下，我们希望了解 组暴露于水环境中的天然和漂白 样品，可电离残基的pK是什么，哪些可电离 基团在光反应循环期间改变它们的质子化状态， 哪些基团与发色团直接相互作用， 蛋白质的各个区域都有分子运动的痕迹。 的情况下 恩镰孢菌素离子载体，我们希望了解化学计量和 金属离子络合物的结构和分子类型 运动发生在脂族和芳族侧链中。 除了 为了阐明这些特殊系统的性质，希望 这些生物物理学研究将为其他膜转运提供模型 系统和整体膜蛋白。 关于此类信息 蛋白质对于我们理解正常的 病理性细胞调节和功能。

Solid-state nuclear magnetic resonance spectroscopy and resonance Raman spectroscopy are to be used as non-perturbative means of studying the structures, dynamics and functional mechanisms of proteins and peptides involved in membrane transport. In particular, we plan to study the purple membrane fragments of the plasma membrane of the halobacterium halobium, which contains a single protein that executes light driven proton transport, and model membranes containing enniatin ionophores, which facilitate passive cation transport. Samples will be isotopically enriched at specific sites to enhance NMR signals of interest, suppress interfering NMR signals, and to induce informative shifts in the resonance Raman spectrum. In the case of the purple membrane, we hope to learn which groups are exposed to the aqueous environment in native and bleached samples, what the pK's of the ionizable residues are, which ionizable groups change their state of protonation during the photo reaction cycle, which groups are in direct interaction with the chromophore, and what types of moleculr motion occur in various regions of the protein. In the case of the enniatin ionophores, we hope to learn what the stoichiometries and structures of the metal ion complexes are and what types of molecular motion occur in the aliphatic and aromatic side chains. In addition to illuminating the properties of these particular systems, it is hoped that these biophysical studies will provide models for other membrane transport systems and integral membrane proteins in general. Information about such proteins is ultimately important to our understanding of normal and pathological cell regulation and function.