Figure 3: Nature Communications

Fig. 3

From: Non-canonical activation of OmpR drives acid and osmotic stress responses in single bacterial cells

Fig. 3

OmpR relieves RpoS repression of yghA during osmotic stress. a mRNA levels of yghA at pHe 7.2 in the presence of 15% sucrose (w/v) were determined by qRT-PCR from wild type, an ompR null strain, an rpoS over-expressed strain, and an ompR/rpoS null strain of S. Typhimurium. Fold expression changes were compared to the wild-type level. Error bars represent the mean ± s.d. (n = 6). b mRNA of yghA at pHe 7.2 in the presence of 15% sucrose (w/v) of an E. coli ompR null strain was compared to the wild-type level. c Representative images of R488/440 are shown after 5 and 90 min incubation at pHe 5.6, or pHe 7.2 + 15% (w/v) sucrose of a yghA null strain, an ompR/rpoS null strain, an ompR/rpoS/yghA null strain, and an ompR null strain of S. Typhimurium with yghA over-expressed. Scale bar, 3 μm. d Plot of the R488/440 ratios of various mutants of S. Typhimurium at each indicated time. Data set is represented as the mean ± s.e.m. (n = 3). The complete graph, including all strains is in Supplementary Fig. 4. e EMSAs were performed with biotin end-labeled yghA and OmpR. f AFM images of yghA 700 from S. Typhimurium with 30 nM OmpR at either acid pH (6.1) or neutral pH (6.8). g Relative height distribution histogram of the yghA promoter complexed with 30 nM OmpR at either acidic or neutral pH