Fig. 4.
Relative expression of plasmid-borne PbudR-gfp in wild-type RVH1, RVH1 splI, RVH1 splI complemented with OHHL, and RVH1 budR grown in LB at pH 7.0 (A); in wild-type RVH1 grown in LB medium at pH 5.5 or 7.0 in the presence or absence of 15 mM acetate (B); and in RVH1 splI grown in LB medium at pH 5.5 in the presence of 0, 3.75, 7.5, or 15 mM acetate or in the presence of 15 mM formate, propionate, or lactate (C). Stationary-phase cultures were diluted 1/100 and exposed for 4 h to the indicated conditions before GFP expression was measured. In each graph, GFP expression of the control strain (i.e., first bar) was arbitrarily set at 100%. Average values and standard deviations for three independent experiments are shown.