Fig. 5
Expression of an inactivated PBP3 during stationary phase inhibits persister formation. Cultures of MG1655 carrying pKG110-ftsI (wild-type ftsI) or pKG110-ftsI* (catalytically inactive mutant) were treated with 100 μM sodium salicylate (inducer) at t = 3 h (a and b). At 24 h, cell cultures were washed to remove the inducer and diluted in fresh LB containing 200 μg/mL ampicillin (a) or 5 μg/mL ofloxacin (b). In (c) and (d) cultures of MG1655 carrying pKG110-ftsITrunc or pKG110-ftsI*Trunc (each devoid of their transmembrane and cytoplasmic domains) were treated as in a and b, and ampicillin (c) and ofloxacin (d) persister assays were carried out. Survival fractions were monitored at the indicated time points. CFU/mL at the indicated time points are provided in Additional file 14: Figure S12E and S12H. * p < 0.05 (t-test). Data represent three or more biological replicates. Each data point was denoted as mean ± s.e