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

GM65440续展重新提交项目摘要 铁元素在生物学中扮演着巨大的角色，包括电子传递反应。 (铁氧还蛋白)、氧的运输和储存(血红蛋白和肌红蛋白)、催化 (固氮酶、P-450、氢酶和数以千计的其他酶)、小分子传感 (尤其是O2、CO和NO)，以及DNA处理和修复。一种与健康相关的 对生物铁的结构和功能有了更好的理解。 克雷默实验室研究的总主题包括使用光谱学作为一种工具 用于生物系统中金属的表征。这项工作的大部分都涉及到应用程序 同步辐射X射线源。多亏了这些资源的巨大改进， 现在可以在稀铁样品上进行灵敏度极高的实验。这些 包括核共振振动光谱(NRVS)技术，这是一种敏感的技术 样品中57Fe的运动。另一种新技术--核共振时域法 干涉测量法(NR-TDI)可以探测样品中所有原子的运动。X-射线实验 国际设施与国内实验室的红外和拉曼测量相辅相成。 今后四年的奋斗目标可以分为三个主题： ·更好地了解处理氢气的酶的催化中间体- [NiFe]和[FeFe]氢酶， ·有关铁-S簇蛋白感测其结构变化的信息 环境，包括mitoNEET和NaF-1，两个与健康相关的蛋白质，它们感知和 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)的蛋白质动力学特征 温度、压力、pH和其他应激源)以Rubredoxin蛋白质为模型 利用NRVS和NR-TDI分别测量铁离子或铁离子的运动 蛋白。 这项研究计划的总体愿景是使用光谱方法来更好地 了解铁是如何在重要的蛋白质中以补充信息的方式使用的 这可以从衍射和显微镜中收集到。在具体的研究过程中 主题，光谱技术，如NRVS，将进一步发展用于生物无机 社区。新的NR-TDI技术将被评估为 有关蛋白质的动态信息。

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.