Glucose can be transported and utilized in Escherichia coli by an altered or overproduced N-acetylglucosamine phosphotransferase system (PTS).

Escherichia coli Δglk ΔmanZ ΔptsG glucose strains that lack the glucose phosphotransferase system (PTS) and the mannose PTS as well as glucokinase have been widely used by researchers studying the PTS. In this study we show that both fast- and slow-growing spontaneous glucose revertants can be readily obtained from Δglk ΔmanZ ΔptsG glucose strains. All of the fast-growing revertants either altered the N-acetylglucosamine PTS or caused its overproduction by inactivating the NagC repressor protein, which regulates the N-acetylglucosamine PTS, and these revertants could utilize either glucose or N-acetylglucosamine as a sole carbon source.