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

• Applicant: Professor Dr. Volker Schünemann
• Subject Area: Biophysics
• Term: from 2016 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 311771384

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.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1927: Iron-Sulfur for Life