Cheng H, Markley J L
Department of Pharmacology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Annu Rev Biophys Biomol Struct. 1995;24:209-37. doi: 10.1146/annurev.bb.24.060195.001233.
Newer NMR methods, particularly in conjunction with stable isotope labeling, offer exciting approaches to structure-function studies of paramagnetic proteins. This review examines progress in NMR spectroscopy of iron-sulfur proteins. The application of multidimensional multinuclear NMR spectroscopy to iron-sulfur proteins and the optimization of NMR pulse sequences for rapidly relaxing spins have allowed investigators to determine sequence-specific assignments for numerous NMR signals in rubredoxins, ferredoxins, and high-potential iron proteins, including those from the cysteine residues that ligate iron ions or iron-sulfur clusters. These advances enable one to interpret the wealth of information derived from NMR parameters, such as the temperature and pH dependence of chemical shifts and the relaxation properties of the resonances that report on interactions between nuclei and between nuclei and unpaired electron density. This information is being used to test theoretical descriptions of electron distribution within these molecules and to model the structures and dynamic properties of the proteins in solution. Mutagenesis of these proteins, in conjunction with NMR studies, is beginning to reveal which residues are important for cluster formation and stability and which residues play a role in electron transfer to and from redox partner proteins.
更新的核磁共振方法，特别是与稳定同位素标记相结合时，为顺磁性蛋白质的结构-功能研究提供了令人兴奋的途径。本综述考察了铁硫蛋白核磁共振波谱学的进展。多维多核核磁共振波谱学在铁硫蛋白中的应用以及针对快速弛豫自旋的核磁共振脉冲序列的优化，使得研究人员能够确定红素氧还蛋白、铁氧还蛋白和高电位铁蛋白中众多核磁共振信号的序列特异性归属，包括来自与铁离子或铁硫簇配位的半胱氨酸残基的信号。这些进展使人们能够解读从核磁共振参数中获得的大量信息，例如化学位移的温度和pH依赖性以及报告核间和核与未成对电子密度间相互作用的共振弛豫特性。这些信息正被用于检验这些分子内电子分布的理论描述，并对溶液中蛋白质的结构和动态特性进行建模。这些蛋白质的诱变结合核磁共振研究，开始揭示哪些残基对簇的形成和稳定性很重要，哪些残基在与氧化还原伙伴蛋白之间的电子转移中起作用。
