The objectives of this proposal are to elucidate the electronic structure and determine the relative positions and orientations of the intermediate electron acceptors in the photosystem I reaction centre. Electron paramagnetic resonance (EPR) spectroscopy will be used to characterise the radical anions of these acceptors. Continuous wave, including high-field, EPR, applied especially to oriented samples, should provide geometric information regarding their relative orientations. Pulsed EPR spectroscopy will be used to detect possible hypefine interactions arising from nearby nitrogen atoms of the protein surrounding. Their 'fingerprint spectra' will form the basis for specific site-directed mutagenesis.
These point mutants should provide an insight into the binding site of the acceptor molecules in the protein especially with regard to their function. This proposal would provide me with a unique opportunity to learn and apply the most powerful techniques of genetic engineering and to perform experiments using the most current approaches of biophysical analysis.