Fig. 4

Viability of Escherichia coli deg31 and host control strains after pre-induction with diverse concentrations of IPTG or 1 mM lactose, before and after incubation with TCP. a Viability of deg31 and E. coli BL21(DE3) with the empty pETDuet and pCDF plasmids as determined by plating of cells pre-induced with different concentrations of IPTG or 1 mM lactose (red columns) before incubation in phosphate buffer with TCP. b Viability of cells after incubation in buffer with 2 mM TCP. Asterisks denote significantly higher (at P < 0.05) cell count of deg31 pre-induced with 1 mM lactose when compared with the count of cells pre-induced with the lowest tested concentration of IPTG (0.01 mM). c Fraction of surviving cells calculated as the difference in the CFUs.ml⁻¹.OD ⁻¹₆₀₀ before and after incubation with TCP. Error bars represent standard deviations calculated from at least four independent experiments. CFU colony forming units