IPTG induction of HB101/pFim2-Ptrc causes a major growth reduction. (A) Growth curves for HB101, HB101/pJTOOL-7 (empty vector), HB101/pFim-Ptrc and HB101/pFim2-Ptrc. The growth curves for HB101 and HB101/pJTOOL-7 are largely superimposed as these are very similar. (B) Growth curves for HB101/pFim2-Ptrc grown for 24 h in LB broth containing 100 μg/ml ampicillin supplemented with 0.0 mM, 0.05 mM or 0.1 mM IPTG. Data shown in all cases represent the means of two biological replicates, each assayed in seven wells (n = 14).