EPR and Mossbauer Characterization of Mn and Fe Proteins

Mn 和 Fe 蛋白的 EPR 和穆斯堡尔表征

• 批准号: 7075580
• 负责人: MICHAEL P HENDRICH
• 金额: $ 19.36万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2010-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7075580
• 关键词: Bacillus; Mossbauer spectrometry; Rhodospirillales; active sites; bacterial genetics; biomimetics; biotin; computer program /software; coryneform bacteria; decarboxylases; electron spin resonance spectroscopy; enzyme activity; enzyme mechanism; enzyme structure; iron compounds; manganese; metalloenzyme; metalloproteins; nitrogenase; oxygenases; protein structure function; site directed mutagenesis; structural biology; transport proteins

DESCRIPTION (provided by applicant): Manganese proteins and enzymes are important in a diverse range of biological functions. The relative amounts and distribution of Mn in humans is known, however, due to the relatively weak binding of Mn, the mechanisms by which Mn can affect human health are only now beginning to be unraveled. Manganese plays an essential role in many cellular processes of both eukaryotes and prokaryotes. Two mononuclear Mn enzymes (Dioxygenase and Acetone Carboxylase) will be investigated in this proposal due to their unique mechanisms of substrate activation. In addition, metal transport and regulation systems are a growing area of study. Recently, a Mn transport regulatory protein (MntR) has been structurally characterized to show a dinuclear Mn site. A spectroscopic characterization of the Mn centers in MntR and how it recognizes DNA in response to Mn will be investigated. A fundamental advance in the interpretation of EPR spectra for both mono- and dinuclear Mn centers will allow an unprecedented ability to quantitatively characterize the active Mn sites of proteins and enzymes. This will be applied to the above proteins, and also for a characterization of the dinuclear Mn enzyme Bacteriophage lambda-Phosphatase. Insight into the mechanism of oxygen and nitrogen activation by Mn and Fe enzymes will be derived from studies of biomimetic complexes. The detection and characterization of intermediates in such mechanisms is critical for an understanding of the mechanism. Two different families of biomimetic complexes and their oxygen or nitrogen derived intermediates will be characterized.

描述（由申请人提供）：锰蛋白质和酶在多种生物功能中很重要。锰在人体中的相对含量和分布是已知的，然而，由于锰的结合相对较弱，锰影响人体健康的机制现在才开始被解开。锰在真核生物和原核生物的许多细胞过程中起着重要作用。两个单核锰酶（双加氧酶和丙酮羧化酶）将在本提案中进行研究，由于其独特的底物激活机制。此外，金属运输和调节系统是一个不断增长的研究领域。最近，锰转运调节蛋白（MntR）的结构特征是显示一个双核锰网站。将研究MntR中Mn中心的光谱表征以及它如何识别DNA以响应Mn。一个根本性的进步，在解释EPR光谱的单核和双核锰中心将允许一个前所未有的能力，定量表征活性锰网站的蛋白质和酶。这将被应用于上述蛋白质，也用于双核锰酶噬菌体胞内磷酸酶的表征。锰和铁酶的氧和氮激活机制的洞察将来自仿生复合物的研究。在这种机制中的中间体的检测和表征对于理解该机制至关重要。两个不同的家庭的仿生复合物和它们的氧或氮衍生的中间体的特点。