Comparison of Glc-PTS activity and PptsG- gfp expression in different chemostat conditions. The distributions show Glc-PTS (PtsG/Crr) activity (orange) based on uptake of a fluorescent glucose analog, expression of PptsG-gfp (green) and negative control (wild-type MG1655, black). Bacteria were grown in minimal media supplemented with D-glucose (Glc), sodium acetate (Ac) or L-arabinose (Ara), at dilution rate D = 0.15 h-1. Some cells expressed the ptsG reporter in conditions when no glucose was taken up via Glc-PTS. Also, low concentration of glucose in the medium feed (first column) led to the existence of a small subpopulation that does not engage in the glucose uptake via Glc-PTS.