A NOVEL FLUORESCENT DERIVATIVE OF GLUCOSE APPLICABLE TO THE ASSESSMENT OF GLUCOSE-UPTAKE ACTIVITY OF ESCHERICHIA-COLI

A novel fluorescent derivative of glucose was synthesized by reacting D-glucosamine and NBD-Cl. The TLC analysis of the reaction mixture sho wed the generation of a single spot with intense fluorescence (lambda( Ex) = 475 nm, lambda(Em) = 550 nm). The obtained novel fluorescent pro duct, which was identified as robenz-2-oxa-1,3-diazol-4-yl)amino)-2-de oxyglucose (2-NBDG) by H-1-NMR and FAB-MS spectrometries, was applied to the assessment of the glucose uptake activity of Escherichia coli B . 2-NBDG accumulated in living cells and not in dead cells. The uptake of 2-NBDG was competitively inhibited by D-glucose and not by L-gluco se, which suggested the involvement of the glucose transporting system in the uptake of 2-NBDG. 2-NBDG taken into the cytoplasm of E. coli c ells was supposedly converted into another derivative in the glucose m etabolic pathway.