SYNTHESIS OF NOVEL IRON & MIXED METAL-SULFUR CLUSTERS

新型铁的合成

• 批准号: 3299723
• 负责人: JEAN LE GALL
• 金额: $ 15.55万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-12-01 至 1993-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3299723
• 关键词: Desulfovibrio; Escherichia coli; catalyst; chemical synthesis; cobalt; computer graphics /printing; eukaryote; ferredoxin; iron; mutagens; oxidation reduction reaction; prokaryote; radiotracer; sulfur compounds; zinc

Iron is the most common transition metal found in proteins and participates in many fundamental physiological functions in all living organisms, in particular in processes related to energy conservation. Among the iron-containing structures which are common to eucaryotes as well as procaryotes, iron-sulfur clusters are extremely important, not only because of their ubiquity, but also because of their unique redox properties. The mechanisms of incorporation and stabilization of iron into these structures is still far from being well understood. Anerobic bacteria, which are important to man in disease and in health, constitute an excellent source of iron-sulfur cluster containing proteins and, as such, are ideal tools for their study. The long term objective of this research project is to understand the conversion mechanisms between three and four iron-containing clusters found in certain ferredoxins and their significance for the regulation of electron flow in multiple electron transfer chains. The use of ferredoxins and artificially reconceived polypeptides as templates for the synthesis of new mixed-metal clusters will also be explored as a means to develop new molecules and examine their potential catalytic properties. Specific aims of this research are: 1) to prepare new mixed-metal clusters incorporated into Desulfovibrio gigas ferredoxin II (a Co-Fe and a Zn-Fe cluster have already been obtained from this protein; 2) to search for other ferredoxins that could perform better than the D. gigas protein in the synthesis of these new metal clusters; 3) to prepare specifically isotope-labelled, either 57 Fe or 56 Fe iron-sulfur clusters and investigate their properties using different spectrometric techniques; 4) to clone and express D. gigas ferredoxin gene in E. coli in order to over-produce the protein for physical studies and also to be able to perform site-directed mutagenesis to understand how 3Fe and 4Fe sulfur clusters are formed and stabilized; 5) to perform physiological experiments with the transformed mixed-metal clusters and the mutated proteins; 6) to extend these techniques to complex metal-containing enzymes; 7) to monitor the above experiments using modern computer graphics modeling.

铁是蛋白质和蛋白质中最常见的过渡金属 参与所有生物的许多基本生理功能 有机体，特别是与节能相关的过程。 在真核生物常见的含铁结构中， 与原核生物一样，铁硫簇极其重要，而不是 不仅因为它们的普遍存在，还因为它们独特的氧化还原作用 特性。 铁的掺入和稳定机制 对这些结构的了解还远远不够。 无氧 细菌对人类疾病和健康都很重要， 是含有铁硫簇的极好来源 蛋白质，因此是他们研究的理想工具。 该研究项目的长期目标是了解 三个和四个含铁团簇之间的转化机制 在某些铁氧还蛋白中发现及其对调节的意义 多个电子转移链中的电子流。 使用 铁氧还蛋白和人工合成的多肽作为模板 还将探索新的混合金属簇的合成 意味着开发新分子并检查其潜在的催化作用 特性。 本研究的具体目标是：1）制备新型混合金属 簇并入 Desulfovibrio gigas ferredoxin II（Co-Fe 并且已经从该蛋白质中获得了 Zn-Fe 簇； 2）到 寻找比 D. gigas 表现更好的其他铁氧还蛋白 这些新金属簇合成中的蛋白质； 3）准备 特别同位素标记的 57 Fe 或 56 Fe 铁硫 簇并使用不同的光谱研究其特性 技术； 4)在大肠杆菌中克隆表达D. gigas铁氧还蛋白基因 为了过量生产用于物理研究的蛋白质，也为了 能够进行定点诱变以了解 3Fe 和 4Fe 硫簇形成并稳定； 5）执行生理 使用转化的混合金属簇和突变的实验 蛋白质； 6）将这些技术扩展到复杂的含金属 酶； 7) 使用现代计算机监控上述实验 图形建模。