Enzyme-Substrate-Cofactor Dynamical Networks Revealed by High-Resolution Field Cycling Relaxometry.

ABSTRACT: The remarkable power and specificity of enzyme catalysis rely on the dynamic alignment of the enzyme, substrates, and cofactors, yet the role of dynamics has usually been approached from the perspective of the protein. We have been using an underappreciated NMR technique, subtesla high-resolution field cycling ³¹P NMR relaxometry, to investigate the dynamics of the enzyme-bound substrates and cofactor on guanosine-5'-monophosphate reductase (GMPR). GMPR forms two dead end, yet catalytically competent, complexes that mimic distinct steps in the catalytic cycle: E·IMP·NADP⁺ undergoes a partial hydride transfer reaction, while E·GMP·NADP⁺ undergoes a partial deamination reaction. A different cofactor conformation is required for each partial reaction. Here we

SUBMITTER: Rosenberg MM 

PROVIDER: S-EPMC8364753 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature