Induction of RpoS-dependent functions in glucose-limited continuous culture: what level of nutrient limitation induces the stationary phase of Escherichia coli?

The expressions of the genes treA and osmY and the quantity of RpoS protein in a glucose-deficient continuous culture of Escherichia coli were studied. Findings indicated that E. coli utilizes a protective stationary-phase behavior when there is not enough glucose to saturate scavenger transporters controlled by cAMP plus endoinducers. The high-level induction of protective functions also elucidated the maintenance energy needed for bacterial growth at low dilution levels.