Spectroscopy of Fe-S Cluster Proteins -- Information for Structure and Function

GM 65440续订重新提交项目摘要 铁元素在生物学中起着巨大的作用，包括电子传递反应 （铁氧化还原素），氧运输和储存（血红蛋白和肌红蛋白），催化 （固氮酶，P-450，氢化酶和数千种其他酶），小分子传感 （特别是O2，CO和NO），以及DNA加工和修复。A的健康相关性 更好地理解生物铁的结构和功能是清楚的。 在克莱默实验室的研究的一般主题涉及使用光谱作为一种工具 用于表征生物系统中的金属。这项工作的大部分涉及应用程序 同步辐射X射线源。由于这些资源的巨大改进， 现在可以在稀释的铁样品上进行灵敏度极高的实验。这些 包括技术核共振振动光谱（NRVS），这是敏感的 57 Fe在样品中的运动。另一项新技术，核共振时域 干涉测量（NR-TDI）可以探测样品中所有原子的运动。X射线实验在 国际设施由家庭实验室的IR和拉曼测量补充。 未来四年的目标可分为三大主题： ·更好地理解处理氢的酶的催化中间体- [NiFe]和[FeFe]氢化酶， ·关于当Fe-S簇蛋白感测到它们时发生的结构变化的信息。 环境，包括mitoNEET和NAF-1，两种健康相关的蛋白质， 传达pH值和氧化还原状态，以及 ·极端微生物（生活在极端环境中的生物体）中蛋白质动力学的表征 温度、压力、pH和其它应激源），使用蛋白质rubredoxin作为模型 系统，并使用NRVS和NR-TDI分别测量Fe或整个 蛋白 这项研究计划的总体愿景是利用光谱方法更好地 了解铁如何在重要的蛋白质中使用，以补充信息的方式 可以通过衍射和显微镜来收集。在研究具体的 主题，光谱技术，如NRVS将进一步发展的生物无机 社区新的NR-TDI技术将作为一种互补探针进行评估， 蛋白质的动力学信息。

GM65440 Renewal Resubmission Project Summary The element iron plays an enormous role in biology, including electron transport reactions (ferredoxins), oxygen transport and storage (hemoglobin and myoglobin), catalysis (nitrogenase, P-450, hydrogenase, and thousands of other enzymes), small molecule sensing (especially O2, CO, and NO), and DNA processing and repair. The health-relatedness of a better understanding of the structure and function of biological Fe is clear. The general theme of research in the Cramer lab involves the use spectroscopy as a tool for characterization of metals in biological systems. Much of this work involves the application of synchrotron radiation x-ray sources. Thanks to enormous improvements of these sources, experiments with exquisite sensitivity can now be conducted on dilute Fe samples. These include the technique Nuclear Resonance Vibrational Spectroscopy (NRVS), which is sensitive to the motion of 57Fe in a sample. Another new technique, nuclear-resonant time-domain interferometry (NR-TDI) can probe motion of all atoms in a sample. The x-ray experiments at international facilities are complemented by IR and Raman measurements at the home lab. The goals for the next 4 years can be divided into 3 main themes: · better understanding of the catalytic intermediates of the enzymes that process hydrogen – [NiFe] and [FeFe] hydrogenases, · information about structural changes that occur when Fe-S cluster proteins sense their environment, including mitoNEET and NAF-1, two health-related proteins which sense and communicate pH and redox status, and · characterization of protein dynamics in extremophiles (organisms that live at extremes of temperature, pressure, pH and other stressors) using the protein rubredoxin as a model system and using NRVS and NR-TDI to respectively measure the motion of Fe or the entire protein. The overall vision of this research program is to use spectroscopic methods to better understand how iron is used in important proteins, in ways that complement the information that can be gathered from diffraction and microscopy. In the course of research on specific topics, spectroscopic techniques such as NRVS will be further developed for the bioinorganic community. The novel NR-TDI technique will be assessed as a complementary probe of dynamical information about proteins.