I am Professor of Structural Biology. I read Biochemistry at York with a final year project using X-ray crystallography to determine the structure of a small bacterial ribonuclease. I continued using X-ray crystallography for my PhD in the Physics Department at Imperial College London with studies of the mechanism of the glycolytic enzyme Glyceraldehyde 3-Phosphate Dehydrogenase. After my PhD I continued to use protein crystallography to investigate enzyme mechanisms at Harvard Imperial College and at York. I took a post at Leicester in 1995 where I work on the structures and mechanisms of redox and other enzymes using X-ray crystallography to determine structures and neutron crystallography in order see the positions of hydrogen atoms. We are currently developing ways to use electron diffraction in time-resolved studies.
We unravel enzyme mechanisms and investigate the way biological molecules recognise both smaller molecules & each other. Using synchrotrons & XFELs X-ray crystallography gives the three-dimensional structures of molecules but the positions of hydrogen atoms are normally invisible. With neutrons we are able to determine the positions of hydrogens. Together neutron & X-ray crystallography allow us get detailed pictures of the interactions of biomolecules. Neutron crystallography has an additional advantage in that it avoids the ionising effects of X-irradiation. We currently use the nuclear reactors in Grenoble and Munich for neutrons & collaborate with the scientists at these facilities. We are also developing ways to use electron diffraction. Because enzyme reactions are dynamic we need ways to trap the intermediates in our crystals and in order to follow the reactions we need to find ways to monitor them. We use single crystal spectrophotometry for our crystal studies. With this we trap intermediates at low temperatures. Because we work with redox sensitive enzymes some of the work is done in our anaerobic glove box this also houses a crystallisation robot.
Kwon et al. (2020) Visualizing the protons in a metalloenzyme electron proton transfer pathway. Proc. Natl. Acad Sci. (USA)117(12):6484-6490.
Kwon et al (2020) Heme peroxidase - Trapping intermediates by cryo neutron crystallography Methods in Enzymology Vol 634 (Ed. P C E Moody) https://doi.org/10.1016/bs.mie.2020.01.010
Moody PCE, Raven EL The Nature and Reactivity of Ferryl Heme in Compounds I and II Acc. Chem Res. 51(2):427-435
Kwon H, et al. (2017) 'Combining X-ray and neutron crystallography with spectroscopy.' Acta Crystallogr D Struct Bio, vol. 73. Pp. 141-147.
Kwon H, et al. (2016) 'Direct visualization of a Fe(IV)-OH intermediate in a heme enzyme.' Nat Commun, vol. 7. P. 13445.
Casadei CM, et al. (2014) 'Heme enzymes. Neutron cryocrystallography captures the protonation state of ferryl heme in a peroxidase.' Science, vol. 345. Pp. 193-197.
Structural Enzymology especially of redox enzymes and enteric pathogen metabolism
BS3070 Structural Biology
Press and media
Royal Society Wolfson Fellow
BA (Biochemistry York) PhD (Biophysics Imperial)