FIG. 3.
Effect of ribosome protection on AZM-mediated killing of stationary-phase cells. (A) Representative growth curves of strain PT5 harboring vector pEX1.8 (strain PT1300) or the ermBP-carrying plasmid pEXERM (strain PT1308) in LB medium. The double-headed arrow indicates the OD600 range for addition of AZM. (B) After addition of AZM or AZM plus MgSO4 at the indicated concentrations, the cultures were incubated at 37°C for 22 h. Viable counts were determined by serial dilutions and plating on LB agar plates. The results are expressed as the means ± standard deviations from three independent experiments.