EPR AND ENDOR OF PARAMAGNETIC BIOMOLECULES

顺磁性生物分子的 EPR 和 ENDOR

• 批准号: 3287211
• 负责人: Charles P. Scholes
• 金额: $ 14.75万
• 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 1994-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3287211
• 关键词: Escherichia coli; cytochrome oxidase; electron nuclear double resonance spectroscopy; electron spin resonance spectroscopy; endonuclease; iron; magnetic field; mitochondria; oxidation; protein structure function; radiotracer; sulfur compounds; Escherichia coli; cytochrome oxidase; electron nuclear double resonance spectroscopy; electron spin resonance spectroscopy; endonuclease; iron; magnetic field; mitochondria; oxidation; protein structure function; radiotracer; sulfur compounds

DESCRIPTION (Adapted from applicant's abstract): The overall goal of this research is to understand how proteins that contain paramagnetic centers work. The applicant will probe the structure of the paramagnetic centers themselves, the interaction between the centers, and the correlation between the structure of the center and its protein surroundings. The systems chosen for study are a protein that recognizes and excises damages from DNA to eliminate potential mutations, proteins that couple transfer of electrons to production of biologically useful energy in mitochondria, and proteins and their models that catalyze biological oxidations. The applicant will focus on probing these centers primarily through the techniques of electron paramagnetic resonance (EPR) (pulsed and continuous) and electron nuclear double resonance (ENDOR) with significant use of other spectroscopic and kinetic methods. The applicant's laboratory is one of the few in the world which routinely uses ENDOR to measure hyperfine couplings of the electron spins in biological molecules. The specific systems to be studied are: (1) Endonuclease III of E. coli which is a DNA repair enzyme that contains, for reasons the applicant intends to discover, an iron-sulfur center. (2) Cytochrome c oxidase, which couples the transfer of electrons to molecular oxygen to the production of biologically useful energy. The applicant intends to probe the electronic mechanisms of this coupling at paramagnetic metals. (3) The mitochondrial cytochrome bc1 complex, which also couples the transfer of electrons through its paramagnetic centers to production of biologically useful energy. The applicant intends to probe the structure of free radicals and paramagnetic metals in the bc1 complex. (4) Cytochrome c peroxidase, which catalyzes the consumption of reduced cytochrome c by peroxide. In consuming peroxide, this enzyme gives rise to an unusual paramagnetic intermediate which the applicant will characterize by using magnetic resonance techniques on genetically manipulated protein. (5) Models for the active sites of copper proteins which catalyze oxidation of substrates or reversibly bind oxygen. As the model structure is varied, the applicant will study the resultant perturbations to electronic structure.

描述（改编自申请人的摘要）：此的总体目标 研究是了解包含顺磁心中心的蛋白质 工作。 申请人将探测顺磁中心的结构 本身，中心之间的相互作用以及相关性 在中心的结构及其蛋白质周围之间。 这 选择进行研究的系统是一种识别和切除损坏的蛋白质 从DNA到消除潜在突变，彼此转移的蛋白质 电子在线粒体中生产生物有用能量的电子，并 蛋白质及其催化生物氧化的模型。 这 申请人将专注于主要通过 电子顺磁共振（EPR）的技术（脉冲和连续） 和电子核双共振（Endor），并大量使用其他 光谱和动力学方法。 申请人的实验室是 世界上少数通常使用Endor来测量超精细的人 电子分子中电子的耦合。 具体 要研究的系统是：（1）大肠杆菌的核酸内切酶III，是DNA 申请人打算发现，修复包含的酶 铁硫心中心。 （2）细胞色素C氧化酶，该酶将 电子向分子氧转移到生物学上的生产 有用的能量。 申请人打算探究 这种耦合在顺磁金属上。 （3）线粒体细胞色素BC1 复合物，也将电子通过其传递 顺磁性集中于生物学上有用能量的产生。 这 申请人打算探测自由基和顺磁性的结构 BC1复合物中的金属。 （4）细胞色素C过氧化物酶，催化 过氧化物减少细胞色素C的消耗。 在消费中 过氧化物，该酶产生异常的顺磁性中间体 申请人将通过使用磁共振来表征哪些 遗传操纵蛋白的技术。 （5）活动的模型 铜蛋白的位点，催化底物的氧化或 可逆地结合氧气。 随着模型结构的变化，申请人 将研究结果对电子结构的扰动。