The effect of inactivation of the glucose phosphotransferase transport system (PTS) on 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) productivity and yield from glucose in Escherichia coli is reported. Strains used in this study were the PTS+ PB103 and its PTS- glucose(+) derivative NF9. Their aroB(-) derivatives PB103B and NF9B were constructed to allow accurate measurement of total carbon flow into the aromatic pathway. The measured specific rates of DAHP synthesis were 0.55 and 0.94 mmol/g-dcw . h and the DAHP molar yields from glucose were 0.43 and 0.71 mol/mol for the PTS+ aroB(-) and the PTS- glucose(+) aroB(-) strains, respectively. For the latter strain, this value represents 83% of the maximum theoretical yield for DAHP synthesis from glucose.