HIGH PRESSURE NMR STUDIES OF PROTEINS AND MEMBRANES

拟议研究的长期目标是阐明 压力对海洋动力学和结构的影响 蛋白质和生物膜。 压力是一个基本的 热力学变量，提供有关过程的信息， 涉及体积的变化，包括折叠和展开 蛋白质、膜中的脂质相变以及 膜的流动性和界面性质。 拟议 工作重点是压力对动力学、相位 几种模型体系：均聚多肽 （聚-L-赖氨酸、聚-L-谷氨酸和聚-N-（3- 羟丙基）-L-谷氨酰胺）、鸡蛋清溶菌酶、抹香鲸 肌红蛋白，和各种纯磷脂的形式，超声 囊泡或多层分散体。 各种先进的高 将采用使用H、H、P核的分辨NMR方法 结合独特的高压NMR探头， 1巴至10千巴和0至100 ℃。 在蛋白质和 将使用同聚肽，选择的1H和13 C共振 研究大分子不同区域的动力学， 来研究折叠-展开的热力学和动力学 过渡。 脂质体中磷脂分子的动力学 将通过13 C NMR进行研究： 酰基链和头基将通过13 C-NMR研究， 使用氘代脂质，并通过H-2D NMR技术： 用~（31）P和~ 1H NMR方法检测变化。 此外，本发明还提供了一种方法， 磷脂的缓慢运动和侧向扩散 脂质体将通过旋转框架NMR弛豫来研究 技术.

The long-term objective of the proposed research is the elucidation of the effects of pressure on the dynamics and structure of proteins and biological membranes. Pressure is a fundamental thermodynamic variable that provides information on processes that involve changes in volume, including the folding and unfolding of proteins, lipid phase changes in membranes, and the modulation of the fluidity and interfacial properties of membranes. The proposed work focuses on the effects of pressure on the dynamics, phase state, and conformation of several model systems: homopolypeptides (poly-L-lysine, poly-L-glutamic acid, and poly-N -(3- hydroxypropyl)-L-glutamine), hen egg-white lysozyme, sperm whale myoglobin, and various pure phospholipids in the form of sonicated vesicles or multilamellar dispersions. A variety of advanced high resolution NMR methods, using H, H, P nuclei, will be employed together with unique high-pressure NMR probes, in the range from 1 bar to 1O kbar and from 0 to, 100 degree C. In the proteins and the homopolypeptides, selected 1H and 13C resonances will be used to study the dynamics in various regions of the macromolecules, and to examine the thermodynamics and kinetics of the folding-unfolding transitions. The dynamics of phospholipid molecules in liposomes will be studied by 13C NMR: the order and con-formation of the acyl chains and the head groups will be investigated by 13C-NMR, using deuterated lipids, and by H-2D NMR techniques: and phase changes will be examined by 31P and H NMR methods. In addition, slow motions and the lateral diffusion of phospholipids in liposomes will be investigated by rotating frame NMR relaxation techniques.