International Collaboration in Chemistry:ELECTRONIC STRUCTURE OF BIOLOGICAL METALLO-CLUSTER AND ITS MAGNETIC INTERPLAY WITH THE PROTEIN SURROUNDING IN THERMOPHILE METALLOENZYMES

国际化学合作：生物金属簇的电子结构及其与嗜热金属酶周围蛋白质的磁相互作用

• 批准号: 1026541
• 负责人: Sergei Dikanov
• 金额: $ 42万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-10-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1026541&HistoricalAwards=false
• 关键词: International; Collaboration; Chemistry; ELECTRONIC; STRUCTURE

This International Collaboration in Chemistry (ICC) award in the Chemistry of Life Processes (CLP) program in the Division of Chemistry supports work by Professor Sergei Dikanov from the University of Illinois at Urbana-Champaign, in collaboration with Dr. Toshio Iwasaki of Nippon Medical School, Japan, and Dr. Takashi Kumasaka of Japan Synchrotron Radiation Research Institute (JASRI)/SPring-8, to study the influence of the protein environment on the electronic structure of the reduced [2Fe-2S] clusters, in which the ligands to the iron(II) site can be (Cys)2, (His)1(Cys)1, or (His)2. This project will explore the complete three-dimensional landscape of the unpaired spin density distribution over the cluster and neighboring key amino acid residues in order to identify the residues having the major influence on the electronic structure of the reduced [2Fe-2S] cluster in hyperthermophilic tractable iron-sulfur proteins. To achieve the goal, a complementary set of multifrequency pulsed EPR approaches will be applied to wild-type proteins, using frozen solutions and single-crystals, and to proteins with uniform and site-specific stable isotopic (2H, 15N, 13C, 57Fe) substitution. The spectroscopic approaches will be combined with ultrahigh-resolution X-ray crystallography, and theoretical calculations. This project will provide excellent training opportunities to young scientists who will gain invaluable multidisciplinary international research experience via bidirectional visits. This project is jointly supported by the NSF and the Japan Society for the Promotion of Science (JSPS).All major electron transfer chains incorporate iron-sulfur clusters, and the environment of the cluster is the main determinant of the redox and/or catalytic activity. Their roles in catalysis of energy conversion are of central importance in photosynthesis, respiration, and many ancillary metabolic processes. Our understanding of these determinants is essential to a deeper knowledge how these processes work, and of critical importance in knowing how to optimize such processes, for example in generation of biofuels.

化学学部生命过程化学（CLP）项目的国际化学合作（ICC）奖支持伊利诺伊大学香槟分校的Sergei Dikanov教授与日本医学院的Toshio Iwasaki博士和日本同步辐射研究所（JASRI）的Takashi Kumasaka博士/春季-8合作开展的工作。研究蛋白质环境对还原[2Fe-2S]簇电子结构的影响，其中铁（II）位点的配体可以是（Cys）2、（His）1(Cys)1或（His）2。本项目将探索团簇和邻近关键氨基酸残基上未配对自旋密度分布的完整三维景观，以确定对超嗜热易处理铁硫蛋白中还原[2Fe-2S]团簇电子结构有主要影响的残基。为了实现这一目标，一套互补的多频脉冲EPR方法将应用于野生型蛋白质，使用冷冻溶液和单晶，以及具有均匀和位点特异性稳定同位素（2H, 15N, 13C, 57Fe）取代的蛋白质。光谱方法将与超高分辨率x射线晶体学和理论计算相结合。该项目将为青年科学家提供良好的培训机会，他们将通过双向访问获得宝贵的多学科国际研究经验。本项目由美国国家科学基金会和日本科学促进会（JSPS）联合资助。所有主要的电子转移链都包含铁硫簇，而簇的环境是氧化还原和/或催化活性的主要决定因素。它们在催化能量转换中的作用在光合作用、呼吸作用和许多辅助代谢过程中起着至关重要的作用。我们对这些决定因素的理解对于更深入地了解这些过程是如何工作的至关重要，并且对于知道如何优化这些过程至关重要，例如在生物燃料的生产中。