substrate inhibition. NADPH and S-adenosyl-L-methionine play antagonistic roles in the allosteric regulation, with NADPH recruiting active forms of the enzyme and S-adenosyl-L-methionine recruiting inactive forms. Enzyme can adopt two states, R and T. NADPH and S-adenosyl-L-methionine exhibit antagonistic binding to a given subunit, so that occupancy by one ligand decreases or abolishes affinity for the other ligand. Within a given state, the subunits do not interact with each other. R-T transitions occur between all similarly ligated states
NADPH and S-adenosyl-L-methionine play antagonistic roles in the allosteric regulation, with NADPH recruiting active forms of the enzyme and S-adenosyl-L-methionine recruiting inactive forms. Enzyme can adopt two states, R and T. NADPH and S-adenosyl-L-methionine exhibit antagonistic binding to a given subunit, so that occupancy by one ligand decreases or abolishes affinity for the other ligand. Within a given state, the subunits do not interact with each other. R-T transitions occur between all similarly ligated states