EPR-ENDOR OF PARAMAGNETIC PROTEINS OF ELECTRON TRANSPORT

电子传输顺磁性蛋白质的 EPR-ENDOR

• 批准号: 3287210
• 负责人: Charles P. Scholes
• 金额: $ 19.55万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT ALBANY
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-12-01 至 1989-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3287210
• 关键词: chemical models; conformation; copper; crystallization; cytochrome P450; cytochrome oxidase; electron density; electron nuclear double resonance spectroscopy; electron spin resonance spectroscopy; electron transport; heme; hemoglobin; hemoprotein structure; magnetic field; metalloproteins; myoglobin; porphyrins; radiotracer

Our goal is to understand the fundamental electronic structure of paramagnetic metal and free radical proteins, to understand the interaction between naturally occuring paramagnetic centers in proteins, and to probe the dynamics of paramagnetic center motion. The outcome of the proposed work will be a more complete understanding of how the paramagnetic centers perform in their biological roles. The specific goals of the proposed research will be: 1. To study Cytochrome P-450 by electron nuclear double resonance (ENDOR) to determine its heme ligand environment. 2. To study by ENDOR the electronic structure at porphyrin-linked nitrogens and protons in ferric hemoglobins, coboglobins, and nitrosyl hemoglobins in order to detect effects of conformational change. 3. To probe by ENDOR the environs of the EPR-detectable "copper" and heme in cytochrome c oxidase and to discover the nature of the ubisemiquinone radical in a newly found radical-ubiquinone protein of the electron transport chain. 4. To probe with pulsed EPR and saturation transfer EPR for evidence of inter-metal interaction and inter-metal distances in cytochrome c oxidase. 5. To look for the effect of slow molecular motions of O2 bound to coboglobins and of the ubiquinone in its protein environment. Pulsed EPR and saturation transfer EPR will be used. To perform these experiments we presently have a working ENDOR spectrometer and modicications for saturation transfer EPR. A pulsed saturation recovery apparatus is now being built to monitor electron spin-lattice relaxation, and a magnetic field pulsing device to operate in conjunction with it will be built as a part of the proposed work.

我们的目标是了解顺磁的基本电子结构 了解金属与自由基蛋白之间的天然相互作用 在蛋白质中出现顺磁中心，并探索 顺磁中心运动。拟议工作的结果将是一个更 完全了解顺磁中心如何在其 生物角色。 拟议研究的具体目标是：1.研究细胞色素 P-450电子核双共振(Endor)测定其血红素配基 环境。2.用Endor方法研究卟啉连接的电子结构 铁血红蛋白、球蛋白和亚硝基中的氮素和质子 以检测构象变化的影响。3.通过以下方式调查 细胞色素c中EPR可检测的“铜”和血红素的环境 并在新的一种新的 发现了电子传递链上的自由基-泛醌蛋白。4.去探查 用脉冲EPR和饱和转移EPR作为金属间化合物的证据 细胞色素c氧化酶中的相互作用和金属间距离。5.寻找 结合在眼球蛋白上的O2的慢分子运动和 在其蛋白质环境中的泛醌。脉冲EPR和饱和转移EPR 将会被使用。 为了进行这些实验，我们目前有一台有效的恩多尔光谱仪， 饱和转移EPR的几点建议。脉冲饱和恢复 现在正在建造一种监测电子自旋-晶格弛豫的设备，以及一个 磁场脉冲装置要与之配合运行，将被建造为 这是拟议工作的一部分。