Research objectives and content
The aa3 cytochrome c oxidase complex (CcO) is the terminal electron carrier in the respiratory chain in eucaryotes and many procaryotes. In this complex 02 is reduced to H20. The CcO protein complex binds two haem groups and three copper atoms. Amino acids in the vicinity of the haem a3 CuB pocket, the center for 02 reduction, are likely to play a crucial role in the function of the CcO complex: they may favour the binding and/or reduction of 02. The conformational flexibility of specific residues may also provide a coupling of the proton pump, a second function of the enzyme, to the redox states of the CcO complex.
This project aims to investigate the ligand-protein interactions in the bacterial aa3 CcO complex using the crystal structure as a reference. Specifically, we will perform absorption difference spectroscopy in the visible on a time range from femtoseconds to milliseconds, and ultrafast infrared and transient Raman spectroscopy on both wildtype and site directed mutated samples. It is proposed to activate the enzyme by ligand dissociation using multi-photon infrared absorption.
Training content (objective, benefit and expected impact)
This work is expected to yield fundamental knowledge about the role of the protein in the function of the CcO complex, and of oxydases in general. The project will provide an opportunity to work with and develop state-of-the-art techniques in a laboratory of high scientific standard. Links with industry / industrial relevance (22)