Role of the phosphotransferase system in Escherichia coli strains deficient in hexose phosphate transport.

In Escherichia coli, glucose 6-phosphate is transported via the Uhp system which is inducible by glucose 6-phosphate. We showed that, in a uhp-deficient strain, glucose 6-phosphate was dephosphorylated in the periplasm and that the resulting glucose was subsequently transported into the cells via the phosphotransferase system. The uptake of glucose generated from glucose 6-phosphate allowed the bacteria to produce an increased level of cAMP compared to cells grown on non-limiting concentrations of glucose.