2-Deoxy-2-Fluoro Glucosides: A Novel Class of Mechanism-Based Glucosidase Inhibitors
Withers, S.G., Street, I.P., Bird, P., and David Dolphin
J. Am. Chem. Soc.
2,4-Dinitrophenyl 2-deoxy-2-fluoro β-D-glucopyranoside was synthesized and demonstrated to be a specific mechanism-based inhibitor for β-glucosidase from Alcaligenes faecalis. The inactivation of the enzyme followed pseudo-1st-order kinetics with a rate const. of 25 min-1 and a dissociation constant of 0.05 mM. Protection against inactivation was shown by the competitive inhibitor isopropylthio β-D-glucopyranoside. Reactivation of the enzyme was observed as expected after removal of free inhibitor and incubation in the presence of substrate. The use of such inhibitors to investigate the intermediacy of a glucosyl enzyme intermediate and to identify the active site residue involved is projected.