Elucidating mechanisms of biological hydrogen conversion through model metalloenzymes

通过模型金属酶阐明生物氢转化机制

• 批准号: 2419343
• 负责人: Hannah Shafaat
• 金额: $ 42.9万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-04-01 至 2024-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2419343&HistoricalAwards=false
• 关键词: Elucidating; mechanisms; biological; hydrogen; conversion

With the support of the Chemistry of Life Processes Program in the Chemistry Division, Professor Hannah Shafaat of The Ohio State University will investigate the factors that govern the activity of nickel-containing enzymes. Reductive nickel enzymes are critical in the metabolic processes of diverse microorganisms and perform valuable reactions such as hydrogen production, carbon dioxide reduction, and methane oxidation. These efficient, complex enzymes operate with high rates and full reversibility but have yet to be accurately reproduced in synthetic systems, leaving many questions unanswered. To better understand native nickel enzymes and learn how to harness this understanding for anthropogenic processes, the Shafaat group will model the nickel-iron hydrogenases using a robust, protein-based scaffold. The proposed studies on the engineered enzymes are aimed at the elucidation of the reaction mechanisms along with the identification of the key factors along the entire protein contributing to catalysis. The research provides insight into how natural enzymes function across a range of length- and timescales. Graduate, undergraduate, and high-school students, including those from underserved communities, will be trained in state-of-the-art research techniques spanning biological, inorganic, physical, and analytical chemistry. This award also supports the development of lectures and hands-on exercises to train members of the broader bioinorganic community who attend the internationally recognized, biennial Penn State Bioinorganic Workshop. This project will be integrated with outreach programs spanning multiple age groups in greater Central Ohio. This project seeks to address critical knowledge gaps about the naturally occurring nickel-iron hydrogenases and related nickel-thiolate enzymes through the development and characterization of a model hydrogenase enzyme, namely nickel-substituted rubredoxin (NiRd). Prior work supported by the NSF in the Shafaat group has established that NiRd is a functional mimic of hydrogenase that exhibits high rates for hydrogen evolution. In the proposed work, spectroscopic techniques, including electron paramagnetic resonance, nuclear magnetic resonance, resonance Raman, and X-ray absorption, coupled with electrochemical methods, will be employed to obtain high-resolution mechanistic information and to reveal molecular-level contributors to hydrogen evolution activity. These studies will provide detailed insight into the layers of control exerted by the protein scaffold in both model and native metalloenzymes. The goals of the work are to identify correlations between enzymatic structure and function and to advance our understanding of biological hydrogen conversion. The research seeks also to identify design principles for highly active artificial metalloenzymes, with long-term implications for the development of sustainable catalysts for small molecule activation reactions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

在化学系生命过程化学项目的支持下，俄亥俄州立大学的 Hannah Shafaat 教授将研究控制含镍酶活性的因素。还原镍酶在多种微生物的代谢过程中至关重要，并执行有价值的反应，例如氢气生产、二氧化碳还原和甲烷氧化。这些高效、复杂的酶具有高速率和完全可逆性，但尚未在合成系统中准确复制，从而留下了许多未解答的问题。为了更好地了解天然镍酶并了解如何利用这种理解来研究人类活动过程，Shafaat 小组将使用强大的基于蛋白质的支架对镍铁氢化酶进行建模。对工程酶的拟议研究旨在阐明反应机制以及识别整个蛋白质中有助于催化的关键因素。该研究深入了解天然酶如何在一系列长度和时间尺度上发挥作用。研究生、本科生和高中生，包括来自服务不足社区的学生，将接受涵盖生物、无机、物理和分析化学的最先进研究技术的培训。该奖项还支持举办讲座和实践练习，以培训参加国际公认的两年一度的宾夕法尼亚州立大学生物无机研讨会的更广泛的生物无机界成员。该项目将与俄亥俄州中部地区跨越多个年龄段的外展计划相结合。该项目旨在通过模型氢化酶（即镍取代红氧还蛋白 (NiRd)）的开发和表征来解决有关天然镍铁氢化酶和相关硫醇镍酶的关键知识差距。 Shafaat 小组先前由 NSF 支持的工作已确定 NiRd 是氢化酶的功能模拟物，具有较高的析氢速率。在拟议的工作中，将采用光谱技术，包括电子顺磁共振、核磁共振、共振拉曼和X射线吸收，与电化学方法相结合，以获得高分辨率的机械信息并揭示氢的分子水平贡献者进化活动。 这些研究将提供对模型和天然金属酶中蛋白质支架所施加的控制层的详细了解。 这项工作的目标是确定酶结构和功能之间的相关性，并增进我们对生物氢转化的理解。 该研究还旨在确定高活性人造金属酶的设计原理，这对小分子活化反应可持续催化剂的开发具有长期影响。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力评估进行评估，被认为值得支持。优点和更广泛的影响审查标准。