FIG. 2.

Gef and ChpBK are bactericidal to E. coli. Cells of E. coli ERAPlacI harboring (A) pUPRIP, (B) pGef, and (C) pChpBK were grown overnight at 37°C and then diluted 1:100 into fresh LB medium containing appropriate antibiotics. At early log phase (OD₆₀₀ of 0.3 to 0.4), the culture was divided equally and incubated in the presence (▪) or absence (□) of 1 mM IPTG. At the indicated times (0, 2, and 4 h postinduction), samples from a dilution series of the culture were plated under repressed conditions on LB plates containing the appropriate antibiotics. Viable counts are expressed as mean CFU, counted on noninductive plates. Each graph is representative of at least two experiments.