Protein Dynamics in the Turnover of Arginine Kinase.
Omar Davulcu 1 , Yu Peng 2 , Rafael Brüschweiler 2 , Jack Skalicky 3 , and Michael Chapman 1
1 Oregon Health and Science University; 2 Ohio State University; 3 University of Utah
Temperature-dependent NMR relaxation dispersion analysis and enzyme kinetics have shown that protein dynamics and turnover share a limiting activation barrier. Comparisons with crystal structures, and their thermal displacements at ambient temperature, indicate that the millisecond motions follow low barrier paths through faster oscillations. To studies of intrinsic motions in substrate-free enzyme, analyses of backbone and side chain motions in Michaelis and transition state analog complexes have recently been added, providing insights into the role of protein dynamics in the turnover cycle.
Following undergraduate studies of Biophysics in London, Michael Chapman’s doctoral studies with David Eisenberg at UCLA involved solving the crystal structure of RuBisCO. Post-doctoral studies with Michael Rossmann at Purdue University involved structural studies supporting anti-rhinoviral drug design, and determination of the structure of canine parvovirus. As an independent investigator at Florida State University, studies of the gene therapy vector, adeno-associated virus (AAV) became a lasting focus, as did the protein dynamics that limit turnover of enzymes like arginine kinase, together combining crystallography, EM, NMR and computational analyses. He moved to OHSU in 2006 as Jones Professor of Structural Biology.