This studentship is for up to 4 years and supported by a Royal Society Wolfson Fellowship
“Traditional” protein X-ray crystallography has contributed enormously to our understanding of enzyme mechanisms. However, hydrogen atoms are not often seen, and the X-rays induce changes that may alter the chemical state of key catalytic components; this is a problem especially for redox enzymes. A number of approaches can be used to avoid some of these difficulties.
One is neutron crystallography, as neutrons can show hydrogen positions and another is to use X-ray free-electron lasers (XFELs) which produce femtosecond pulses of X-rays, allowing diffraction data to be collected before damage can take place. Developments and improvements at synchrotron sources now let us collect diffraction data from very small crystals in milliseconds at room temperature. Electron crystallography is advancing quickly and could lead to detailed description of the electrostatic surfaces in enzyme active sites.
Using single crystal spectroscopy and neutron crystallography we have been able to see the hydrogen positions in catalytic intermediates of heme peroxidases. This project aims to take advantage of the latest exciting developments in structural biology techniques to explore the catalytic mechanisms of these and other redox enzymes. LISCB is well equipped for structural biology (see https://www2.le.ac.uk/institutes/liscb/facilities-and-technologies ). We expect to undertake external experimental work at the Diamond Light Source synchrotron near Oxford, the Neutron sources in Grenoble, Munich or Tennessee, and the XFELs in Japan and Hamburg.
• Casadei CM, et al. (2014) 'Heme enzymes. Neutron cryocrystallography captures the protonation state of ferryl heme in a peroxidase.' Science, 345. Pp. 193–197.
• Kwon H, et al. (2016) 'Direct visualization of a Fe(IV)-OH intermediate in a heme enzyme.' Nat Commun, vol. 7. P. 13445.
Moody, PCE & Raven EL (2018) The Nature and Reactivity of Ferryl Heme in Compounds I and II Acc. Chem. Res. 51 (2), pp 427–435
Professor Peter Moody
Dr Jaswir Basran