The use of deoxyfluoro-d-glucopyranoses and related compounds in a study of yeast hexokinase specificity

Abstract

1. 2-Deoxy-2-fluoro-d-glucose, 2-deoxy-2-fluoro-d-mannose and 2-deoxy-2,2-difluoro-d-arabino-hexose are good substrates for yeast hexokinase. 2. 3-Deoxy-3-fluoro-d-glucose and 4-deoxy-4-fluoro-d-glucose are poor substrates and have very similar Km values (8×10−2m). 3. Neither α- nor β-d-glucopyranosyl fluoride is a substrate or inhibitor. 4. Studies with 2-chloro-2-deoxy- and 2-O-methyl derivatives of d-glucose and d-mannose have revealed that little chemical modification is possible at position 2 without substantial loss in substrate binding. 5. The variation in the value of Km for the d-hexose derivatives was associated with a corresponding change in the value of Km for MgATP2− showing that the binding of MgATP2− is modified by the binding of the sugar.