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We have several research themes in the group, all of which are underpinned by the study of unpaired electrons. We use electron paramagnetic resonance (EPR) spectroscopy (in combination with other techniques) as a powerful method for obtaining detailed information on the structure, function, reactivity and environment of these ubiquitous spin centres.
(1) We make use of chemical principles to understand fundamentally important reactions in biology. Reduction-oxidation (redox) reactions underpin innumerable chemical reactions and much of the chemistry of life. Many redox reactions proceed via radical intermediates and these are often located in mechanistically key locations (see our recent book chapter). We investigate how oxidation-state changes govern respiration (respiratory complex I) and photosynthesis (photosynthetic complex I) and how nature has fine-tuned the redox properties of its many intricate molecular machines. Membranes play a fundamentally important role for many proteins and we are investigating the role of membranes on protein activity and function through spin labels and protein-intrinsic paramagnetic centres.
(2) We are developing film-electrochemical EPR (FE-EPR) as a new method to study the evolution of radicals during redox and catalytic reactions in real time. This enables detailed and previously impossible mechanistic understanding of both chemical and biochemical reactions. The catalytic reactions we investigate range from well-known long-established chemical transformations such as nitroxide-catalysed alcohol oxidation, to complex metal-containing enzymes that may prove to be novel targets for the development of new antimicrobials. Our FE-EPR methodology is even finding applications in battery research.
(3) Radicals often hold key mechanistic information - but trapping them in sufficient numbers for detailed EPR investigations can be a major challenge. We specialise in working with minute sample concentrations and volumes, and are seeking to make the impossible possible with our current collaborative grant SpinSUPER.
PhD opportunities available for entry in 2023:
- Apply here for our rEaCt CDT project "Harnessing reactive radical intermediates to design new and more sustainable catalysts"
- Apply for a Chemistry Departmental scholarship (details here - UK students only)
- Apply for the Imperial-CSC scholarship (Chinese and Hong Kong students only)
We have a track record in supporting talented students in securing highly competitive scholarships.
Maxie completed her DPhil on EPR spectroscopic investigations of Fe-S cluster relays in enzymes at Oxford in 2012 under the supervision of Prof. Fraser Armstrong FRS, started her independent career at Queen Mary University of London in 2013 and moved to Imperial College in April 2019.
She secured >£4M as Principal Investigator and leads an £2.3M EPSRC strategic equipment project, establishing a Centre of Pulse ESR spectroscopy (PEPR) at Imperial College, of which she is the Director. She is passionate about contributing to the EPR community internationally and is currently Vice President (for Europe) of the International ESR Society. Maxie was the recipient of the EuroBIC Medal in 2022 and the President's Medal for Excellence in Research in 2023.
Maxie has two children, born in 2013 and 2018.
et al., 2023, Using light scattering to assess how phospholipid-protein interactions affect complex I functionality in liposomes, Rsc Chemical Biology, Vol:4, ISSN:2633-0679, Pages:386-398
et al., 2022, Bio-electrocatalytic conversion of food waste to ethylene via succinic acid as the central intermediate, Acs Catalysis, Vol:12, ISSN:2155-5435, Pages:13360-13371
et al., 2022, Radical-SAM dependent nucleotide dehydratase (SAND), rectification of the names of an ancient iron-sulfur enzyme using NC-IUBMB recommendations, Frontiers in Molecular Biosciences, Vol:9
et al., 2022, Controlling and exploiting intrinsic unpaired electrons in metalloproteins, Methods in Enzymology, Vol:666, ISSN:0076-6879, Pages:233-296
et al., 2022, Following the evolution of paramagnetic species during catalysis: film-electrochemical EPR spectroscopy, 21st European Bioenergetics Conference (EBEC), ELSEVIER, Pages:49-49, ISSN:0005-2728