FIG. 3.

Effect of medium osmolarity on colony formation by strain VC6129 (ΔrelA251::kan). Nutrient agar plates containing the indicated amounts of NaCl were inoculated with a series of dilutions of an exponential-phase culture of strain VC6129. Duplicate sets of plates were prepared for each salt concentration, with one set incubated at 30°C and the other incubated at 42°C. Colonies were counted after 36 h of incubation, and plating efficiencies (colony count at 42°C divided by colony count at 30°C) were calculated for each salt concentration.