PARAMAGNETIC NMR OF ELECTRON TRANSFER COPPER PROTEINS

电子传递过程是生命现象的关键步骤 例如DNA合成和有氧呼吸。电子转移事件 发生在蛋白质中的远距离辅基之间，例如铁- 硫簇、血红素单元、黄素和铜中心。 后者 包括蓝铜和CuA单元，设计用于执行 有效的远程电子转移。 这种效率似乎是 与这些金属位点的电子结构高度相关。 蓝色 铜中心具有单核刚性结构， Cu（II）或Cu（I）离子。 CuA位是一个混合价态的配位体， 显示不寻常的电子结构的单位。 父母补助金的主要目标是确定结构因素， 控制钌标记的铜和铁中的电子转移速率 proteins. 本项目的总体目标是揭示 负责蓝铜的ET特性的结构特征， 顺磁核磁共振波谱法研究蛋白质中的CuA中心 天然和突变铜蛋白的研究，其中不同的金属 配体已被取代。 顺磁NMR能够识别 金属配体，并提供电子自旋密度到每个原子核上 属于配位残基。 电子转移 在突变蛋白质的性能将分析在光 这些研究。

Electron transfer processes are key steps of vital biological phenomena such as DNA synthesis and aerobic respiration. Electron transfer events take place in proteins between distant prosthetic groups such as iron- sulfur clusters, heme units, flavins and copper centers. The latter comprise the blue copper and CuA units, designed for performing efficient long range electron transfer. This efficiency seems to be highly related to the electronic structure of these metal sites. Blue copper centers possess mononuclear rigid structures able to accommodate either Cu(II) or Cu(I) ions. The CuA site is a mixed-valence bimetallic unit displaying an unusual electronic structure. The broad goal of the parent grant is to define the structural factors that control electron transfer rates in Ru-labeled copper and iron proteins. The broad objective of the present project is to uncover the structural features responsible for the ET properties of blue copper and CuA centers in proteins by means of paramagnetic NMR spectroscopic studies of native and mutated copper proteins in which different metal ligands have been replaced. Paramagnetic NMR is able to identify the metal ligands and to provide the electron spin density onto each nuclei belonging to the coordinated residues. The electron transfer performance in the mutant proteins will be analyzed at the light of these studies.