FIG. 7.
Cross-activity of toxRVc and toxRVv in the stimulation of the ctx promoter in an E. coli background. Both genes were cloned into expression vector pBAD24 and transformed into E. coli VM2 with a ctx promoter-lacZ fusion in the chromosome. Cultures were induced by 0.2% arabinose at time zero. Each error bar indicates the standard error of the mean of triplicate experiments. Symbols: × and ⧫, E. coli VM2 without plasmids, before and after induction, respectively; ▵ and ▴, VM2 carrying pBAD24, before and after induction, respectively; ○ and ●, VM2 carrying pCMM610, before and after induction, respectively; □ and ■, VM2 carrying pCMM651, before and after induction, respectively.