Assembly of Biological Iron-Sulfur Clusters

生物铁硫簇的组装

• 批准号: 6869789
• 负责人: MICHAEL K. JOHNSON
• 金额: $ 24.14万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6869789
• 关键词: Mossbauer spectrometry; Raman spectrometry; X ray crystallography; biosynthesis; circular magnetic dichroism; electron spin resonance spectroscopy; electrospray ionization mass spectrometry; genetic regulation; genetic transcription; iron metabolism; iron sulfur protein; molecular assembly /self assembly; molecular biology; molecular chaperones; operon; Mossbauer spectrometry; Raman spectrometry; X ray crystallography; biosynthesis; circular magnetic dichroism; electron spin resonance spectroscopy; electrospray ionization mass spectrometry; genetic regulation; genetic transcription; iron metabolism; iron sulfur protein; molecular assembly /self assembly; molecular biology; molecular chaperones; operon

DESCRIPTION (provided by applicant): Iron-sulfur clusters are present in more than 160 different types of enzymes or proteins and constitute one of the most ancient, ubiquitous and structurally diverse classes of biological prosthetic groups. Hence the process of iron-sulfur biosynthesis is essential to almost all forms of life and is remarkably conserved in prokaryotic and eukaryotic organisms. Three distinct types of iron-sulfur cluster assembly machinery have emerged, termed the NIF, ISC and SUF systems, and in each case the overall mechanism involves cysteine desulfurase-mediated assembly of transient clusters on scaffold proteins and subsequent transfer of preformed clusters or cluster fragments to apo proteins. However, in no case is the assembly or transfer mechanism understood at the molecular level. The long-term goal of this project is a molecular-level understanding of iron-sulfur cluster biosynthesis in the NIF, ISC and SUF systems. Elucidating the mechanism of Fe-S cluster biosynthesis is central to understanding cellular iron homeostasis and thereby human diseases associated with iron-overload and defects in the mitochondrial respiratory chain. The approach involves using molecular biology techniques to effect large scale expression and/or site specific changes in the target enzymes and proteins, biochemical and enzymatic assays, x-ray crystallography, and the application of biophysical spectroscopic techniques (electron paramagnetic resonance, electronic absorption and magnetic circular dichroism, resonance Raman, Mossbauer and mass spectrometry) that can probe the nature and detailed properties of iron or iron-sulfur centers during cluster biosynthesis. The objectives are to establish the structure of cluster-bound forms and the molecular mechanism of cluster assembly and transfer for each the three known types of iron-sulfur cluster scaffold proteins, characterize the mechanism of regulation of iron-sulfur cluster biosynthesis, and identify hitherto in characterized scaffold proteins specific of the assembly of cubane [4Fe-4S] clusters.

描述（由申请人提供）：铁硫簇存在于160多种类型的酶或蛋白质中，构成了最古老，无处不在和结构上多样化的生物假体群体之一。因此，铁硫生物合成的过程对于几乎所有形式的生命都是必不可少的，在原核和真核生物中是明显的。已经出现了三种不同类型的铁硫簇组装机械，称为NIF，ISC和SUF系统，在每种情况下，总体机制都涉及半胱氨酸脱硫化酶介导的瞬态簇在骨架蛋白上的瞬态簇的组装，并随后转移了预制的插图或群集片段向Apo Protein的转移。但是，在任何情况下，在分子水平上都理解了组装或转移机制。该项目的长期目标是对NIF，ISC和SUF系统中铁硫簇生物合成的分子水平的理解。阐明Fe-S簇生物合成的机制对于了解细胞铁稳态以及与线粒体呼吸链中的铁超载和缺陷相关的人类疾病至关重要。该方法涉及使用分子生物学技术来实现靶酶和蛋白质中的大规模表达和/或现场特定的变化，生化和酶测定，X射线晶体学以及生物物理光谱光谱技术的应用探测簇生物合成期间铁或铁中心的性质和详细特性。 The objectives are to establish the structure of cluster-bound forms and the molecular mechanism of cluster assembly and transfer for each the three known types of iron-sulfur cluster scaffold proteins, characterize the mechanism of regulation of iron-sulfur cluster biosynthesis, and identify hitherto in characterized scaffold proteins specific of the assembly of cubane [4Fe-4S] clusters.