FIG 6.

Activation of PcomX by inducible comRS in E. coli. Activity of a PcomX-gfp reporter within individual E. coli cells was measured by fluorescence microscopy. (A) Strains harbored a two-plasmid system that included the PcomX-gfp reporter as well as different combinations of comR and comS under the control of the T7-lac promoter. (B) GFP fluorescence of controls containing the pACYC-Duet1 empty vector, comR alone, or comS alone after 3 h of growth with shaking, following addition of 0, 300 µM, and 1 mM IPTG. (C) GFP fluorescence of the strain possessing both comR and comS after 3 h of growth with shaking in various IPTG concentrations. The blue bar represents the median cell fluorescence.