Figure 1.

TisB-dependent stabilization of the persister state. Persister cells arise from exposure to a fluoroquinolone antibiotic (drug-induced persisters, red) from non-persister cells (blue) by expression of TisB or by other factors. Persisters may also exist before treatment (yellow). During treatment, accumulation of the TisB toxin has a stabilizing effect on the persister state. This probably affects both drug-induced persisters (red) and pre-existing persisters formed by other factors (striped red/yellow). Survival probability increases as the persister state is prolonged beyond the duration of antibiotic treatment. Non-stabilized persisters (yellow) have a higher probability for premature awakening and will be eliminated (pale yellow). Only cells that remain sufficiently long in the persister state can successfully contribute to population recovery after treatment. The arrows at the bottom represent key events as well as primary and secondary effects of TisB expression in Escherichia coli wild-type cultures. A solid line indicates mostly confirmed time points for an event, while a dotted line indicates that an event is likely to have already occurred at that time point but no corresponding data are available.