Mössbauer spectroscopic methods to study iron-sulfur assembly, disassembly and catalysis

在这个项目的框架内，我们希望通过穆斯堡尔谱来澄清铁-硫中心的功能相关、电子和结构性质。利用实验室中常规的穆斯堡尔谱，我们确定了新发现的蛋白质中的铁-硫中心，研究了底物与酶活性铁-硫中心的结合，并研究了铁-S中心在整个细胞中的组装。利用强磁场下的穆斯堡尔谱，我们特别确定了抗磁性的Fe-S中心及其与NO等配体的相互作用。借助基于同步加速器的核非弹性散射(NIS)，也称为核共振振动光谱(NRVS)，实验研究了铁硫中心的振动。利用基于结构模型的量子化学方法计算了分子的振动模式。在第一个资助期的第一次成功实验之后，我们希望继续将这一方法应用于模型络合物的单晶以及更复杂的铁硫蛋白，如固氮酶。

Within the framework of this project, we want to contribute to the clarification of function-relevant, electronic and structural properties of iron-sulfur centers by means of Mössbauer spectroscopy. Using conventional Mössbauer spectroscopy in the laboratory, we identify iron-sulfur centers in newly discovered proteins, study the binding of substrates to enzymatically active iron-sulfur centers, and investigate the assembly of Fe-S centers in whole cells. Using Mössbauer spectroscopy in high magnetic fields we identify in particular diamagnetic Fe-S centers and their interaction with ligands such as NO. With the help of synchrotron-based Nuclear Inelastic Scattering (NIS), also called Nuclear Resonance Vibrational Spectroscopy (NRVS), vibrations of the iron-sulfur centers are experimentally investigated. Using quantum chemical methods based on structural models the vibrational modes are calculated. After first successful experiments during the 1st funding period we want to continue applying this methodology to single crystals of model complexes as well as to more complex iron-sulfur proteins such as nitrogenase.