|
Our Field of Research
The research of our group focuses on those chemical processes that are responsible for the energy supply of living cells.
In order to understand the molecular basis of energy transduction, we have extensive interest in experiments which reveal at the molecular level how protons are drawn through proteins. It is crucial to determine the pK value of the crucial amino acid side chains and to define the structural, dynamic and energetic requirements for the proton transferring groups in the proton pumping enzymes and the cofactor sites that rule them.
Reaction induced FTIR difference spectroscopy is used to enable the observation of protein action at the level of single functional groups within huge proteins. The combination of chemical specificity of infrared spectroscopy with an electrochemical approach in the mid infrared, is applied to monitor protonation reactions coupled to electron transfer providing essential knowledge’s on structure, function and dynamics and finally for the understanding of the mechanism.
The use of the so called mid infrared spectral range is well established for the study of the protonation state of individual acidic residues, determination of secondary structure elements or biological membranes.
Studies at lower frequencies (< 800 cm-1), however, are just starting to evolve. This spectral range includes interesting contributions from metal-ligand vibrations, like the Fe-S vibration in iron sulfur clusters, protonation dependent vibrations of aromatic rings as well as breathing modes from the overall protein. At lower frequencies, signals from hydrogen-bonding interaction and ‘breathing’ modes can be expected. Infrared spectroscopy with conventional and synchrotron light sources are being elaborated and applied on the characterization of the cofactors in soluble and membrane proteins from the respiratory chain of different organisms.
|
