Replacement EPR spectrometer to the multiuser Biomedical EPR Facility at the University of Essex

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We propose to replace the current Electron Paramagnetic Resonance (EPR) spectrometer, at the Biomedical EPR Facility at the University of Essex, with the latest state of the art X-band spectrometer with capabilities for future upgrades.EPR spectroscopy allows detection of molecules in the states, called paramagnetic, that are formed in all oxidation/reduction reactions. These paramagnetic states, of which the best known are free radicals, can be transient (with either short or long life time) or stable. The processes of paramagnetic states formation within enzymes and proteins, as well as their disappearance, are of great interest since the sequential events of one type of paramagnetic centre transforming into another can be followed in time, thus providing a picture of the molecular mechanism revealing how an enzyme works. Such information is important for understanding a wide range of biological processes.The current EMX EPR spectrometer (Bruker) is 23 years old and has developed a serious intermittent fault. Throughout these years, the Biomedical EPR Facility has contributed significantly to the research focused on proteins and enzymes conducted by a range of research groups in the UK. The Facility has developed highly specialised expertise in protein-based free radicals and metallo-proteins and enzymes. Our in-house built apparatus for freezing samples for EPR spectroscopy of rapid reactions between enzyme and substrate (funded by BBSRC, BB/E02355X/1), allows valuable kinetic data pertaining to the appearance and transformation of paramagnetic species over a reaction time course to be obtained. Such data sets can be used in computer generated kinetic models to verify hypotheses about the enzyme mechanism.To maintain the high quality output of the Facility documented in publications, grant awards and staff training, we require an EPR spectrometer of a similar class (E500 Bruker) but with substantial advantages compared to the current model, namely: a) up-to-date electronics and software package; b) the system can be upgraded in the future to operate at a second working frequency and a pulsed regime.The consortium of applicants consists of 11 academics from two Schools of the University of Essex and 8 external collaborators, all with excellent international reputations in their fields. The scope of research by these scientists is wide but all require EPR spectroscopy as a method for their research.The proposal features 10 projects that require and will benefit greatly from the capabilities of the requested instrument:1. Exploring the biotechnological potential of Streptomyces lividans enzymes2. Electron transfer through and between proteins3. Kinetics of the phase transition in thermoresponsive smart materials on temperature jump4. Integrated time-resolved EPR and time-resolved crystal structures of metalloproteins5. Deep neural network analysis of the EPR spectra of enzymes and proteins6. Dynamics of membrane proteins sequestered in polymer based lipid particles7. New biochemistry of bacterioferritin8. De novo haem peroxidases9. Iron deficiency in diet and cardiac muscle tissue respiration10. New transporter-like membrane protein from StreptomycesThe existing Bruker EMX spectrometer at the Biomedical EPR Facility at Essex has been the key instrument in producing high quality publications and obtaining grant awards with a clear upward trajectory of funds and research outputs over the period of the Facility existence. The replacement spectrometer would ensure that our world leading position in EPR spectroscopy of biomolecules will be maintained.