PARAMAGNETIC NMR OF ELECTRON TRANSFER COPPER PROTEINS

电子传递过程是生命生物现象的关键步骤 例如DNA合成和有氧呼吸。电子转移事件 发生在遥远的假体基团之间的蛋白质中，例如铁- 硫簇、血红素单元、黄素和铜中心。后者 由蓝铜和CUA单元组成，旨在执行 高效的长距离电子转移。这种效率似乎是 与这些金属位置的电子结构高度相关。蓝色 铜中心具有单核刚性结构，能够容纳 铜(II)或铜(I)离子。CuA位是混合价双金属 显示出不寻常的电子结构的单元。 母基金的总体目标是确定结构性因素 控制着Ru标记的铜和铁中的电子转移速率 蛋白质。本项目的广泛目标是揭示 影响蓝铜电致发光性能的组织特征 用顺磁核磁共振波谱研究蛋白质中的CuA中心 不同金属含量的天然和突变铜蛋白的研究 配体已被替换。顺磁核磁共振能够识别 金属配体，并提供每个原子核上的电子自旋密度 属于配位残基的。电子转移 突变蛋白的性能将根据以下条件进行分析 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.