Inhibition by 3-deoxy-3-fluoro-D-glucose of the utilization of lactose and other carbon sources by Escherichia coli.

Abstract

Summary: 3-Deoxy-3-fluoro-D-glucose (3FG) was converted to 3FG-6-phosphate by the phosphoenolpyruvate-dependent phosphotransferase system in frozen and thawed Escherichia coli. Up to 0.03g 3FG was taken up/g bacterial dry wt. Uptake of 3FG was not lethal, though 3FG at 0.1 to 10 mM completely prevented or severely inhibited utilization of lactose, fructose, glycerol, succinate, acetate and pyruvate. It prevented lactose utilization by inhibition of the synthesis and activity of both β-galactosidase and galactoside permease. 3FG-resistant mutants were isolated which were deficient in the Enzyme II of the phosphoenolpyruvate-dependent phosphotransferase system specific for glucose and for 3FG. Our findings support the view that the ‘glucose effect’ may depend upon glucose itself or a glucose derivative, rather than upon catabolic products.