FIG. 3.

Envelope permeability of ompR malT(Con) mutants. (A) Inner membrane permeability of WT (AJW678) (circles), ompR (AJW2050) (squares), malT(Con) (AJW3499) (triangles), and ompR malT(Con) (AJW3098) (diamonds) mutants. Cells were grown in LB at 37°C. At regular intervals, samples were taken for OD readings and β-galactosidase measurements as described in Materials and Methods. Upper panel, growth curves. Lower panel, percent β-galactosidase activity. Values represent the mean of triplicates. Error bars indicate standard deviations and are shown only when greater than the size of the symbol. (B) Outer membrane permeativity of ompR malT(Con) mutants. Cells were grown in LB at 37°C. After 150 min (left panel) and 400 min (right panel), cells were harvested, stained with Nile red, and observed under a fluorescence microscope. The total cell numbers in the two images are identical.