CAREER: Metalloenzyme mechanisms probed by resonance Raman spectroscopy

金属是所有蛋白质中约50%的基本成分，具有从能量储存和代谢到分子运输和细胞信号传递的一系列功能。然而，由于这些金属蛋白系统的复杂性，其中许多包含多个不同的金属中心，作用机制往往仍然难以捉摸。这项研究将开发一种新的方法来研究这些反应，将实验室实验与计算化学相结合，以更好地了解这些金属蛋白的功能。这一方法将被应用于天然和工程酶中氢气产生和氧化的研究，以及未来在替代能源、可持续燃料、二氧化碳固定和氮循环等方面的潜在应用。此外，这项建议的研究目标与教育和外联活动相结合，对科学和社会都产生了深远的影响。这项工作的跨学科性质，涉及生物、化学和物理的方方面面，使这个主题可以接触到各种各样的观众。该教育计划将以身临其境的方式让来自未被充分代表的种族/民族和残疾学生的广泛学生接触现代化学研究，目的是建立一条多样化的、面向职业的STEM人才渠道。在俄亥俄州立大学和世界各地开展的当代研究中，将为成人观众举办普遍感兴趣的研讨会，目的是提高科学素养，提高认识，并更好地让社区参与到当代研究中来。俄亥俄州立大学的汉娜·沙法特博士获得了化学系生命过程化学计划的这一奖项，他将利用计算引导的共振拉曼光谱(CGRRS)研究金属蛋白中的酶机制。通过利用在高度可调的最先进仪器上执行的共振拉曼光谱的选择性和灵敏度，将获得关于催化中间体的结构的重要信息，包括质子化状态、键序和配位模式。位置选择性和状态特定的激发结合光谱性质的理论预测将被用来表征传统方法无法获得的中间体和瞬时物种。将研究金属酶活性部位的小分子活化反应，包括氢酶和模型中的质子还原、氢氧化和氧还原，以演示这种实验-计算方法的有效性，并确定催化过程中的关键结构基序。这种协同方法将广泛适用于多种类型的酶的研究，特别是那些含有多种金属辅酶因子的酶，如固氮酶和一氧化碳脱氢酶。使用CGRRS，将有可能在分子水平上深入了解复杂的反应机制，并开始了解金属蛋白如何能够作为一些已知的最有效的催化剂发挥作用。

Metals are an essential component of approximately 50% of all proteins, with functions ranging from energy storage and metabolism to molecular transport and cellular signaling. However, due to the complexity of these metalloprotein systems, many of which contain multiple, distinct metal centers, the mechanisms of action often remain elusive. This research will develop a novel approach towards studying these reactions by combining laboratory experiments with computational chemistry to better understand how these metalloproteins function. This methodology will be applied to the study of hydrogen production and oxidation in natural and engineered enzymes, with future potential applications for alternative energy, sustainable fuels, carbon dioxide fixation, and nitrogen cycling, among others. Furthermore, the research objectives of this proposal are integrated with education and outreach activities, with far-reaching impact for both science and society. The interdisciplinary nature of the work, involving aspects of biology, chemistry, and physics, renders the subject accessible to a wide variety of audiences. The educational plan will expose a broad range of students from underrepresented racial/ethnic groups and with disabilities to modern chemistry research in an immersive fashion, with the objective of building a diverse, career-oriented pipeline of STEM talent. General-interest seminars for adult audiences will be presented with aims of improving scientific literacy, increasing awareness, and better engaging the community in contemporary research being carried out at OSU and across the world.With this award from the Chemistry of Life Processes Program in the Division of Chemistry, Dr. Hannah Shafaat from The Ohio State University will study enzymatic mechanisms in metalloproteins using computationally-guided resonance Raman spectroscopy (CGRRS). By harnessing the selectivity and sensitivity of resonance Raman spectroscopy performed on a highly tunable, state-of-the-art instrument, important information on the structures of catalytic intermediates, including protonation state, bond order, and coordination mode, will be obtained. Site-selective and state-specific excitation in conjunction with theoretical predictions of spectroscopic properties will be used to characterize intermediates and transient species that are inaccessible by conventional approaches. Small molecule activation reactions at metalloenzyme active sites, including proton reduction, hydrogen oxidation, and oxygen reduction in hydrogenases and models, will be investigated to demonstrate the utility of this experimental-computational approach and identify key structural motifs during catalysis. This synergistic methodology will be broadly applicable to the study of many classes of enzymes, particularly those containing multiple metallocofactors, such as nitrogenase and carbon monoxide dehydrogenase. Using CGRRS, it will be possible to gain molecular-level insight into complex reaction mechanisms and begin to understand how metalloproteins are able to function as some of the most efficient catalysts known.