Fig. 5.

Comparison of flaA promoter activity during intracellular and extracellular growth in the presence or absence of MogR. Murine J774 cells were infected at 27°C with strain EGDe flaA::Tn or EGDeΔ674 flaA::Tn, containing a flaA promoter-lacZ fusion, or strain EGDe pHPL3-lacZ, containing a constitutive HyperSPO1-lacZ promoter fusion. β-galactosidase activity from bacteria grown within host cells (dark shaded bars) was determined and compared with β-galactosidase activity from bacteria grown in BHI broth (light shaded bars). β-galactosidase activities depicted represent the means plus SD of three individual experiments. The numerical value of the mean for each condition is also given below the bar graphs.