Fig. 9.

RNAP occupancy across kdp operons is affected under different conditions, and kdp expression sensitizes cells to MG stress.

A. Shown in blue are ChIP-chip data from MG1655 cells, grown to mid-exponential phase, in K_0.2 medium relative to cells grown in K₁₁₅ medium. Three independent experiments were performed and shown are representative data. Shown in red are ChIP-chip data from MG1655 cells grown in K_0.2 medium and exposed to a sublethal MG concentration relative to untreated cells during mid-exponential growth (Type I experiment). Shown in black are equivalent data to the ones shown in red except that experiments were performed with strain MJF632 (ΔkefGB, ΔkefFC). Four independent experiments were performed and shown are representative data. Data smoothing and labels for all ChIP-chip data as in Fig. 3.

B. kdpA transcript levels in strain MG1655 grown in different minimal media as determined by qRT-PCR. Transcript levels were normalized against the internal control genes topB, trkA and polA. Shown are the averages and standard deviations of three independent experiments.

C. Cell viability of strains MG1655 (filled diamonds) and MG1655ΔkdpA (open diamonds) in K_0.2 medium upon MG challenge. Error bars indicate the standard deviation of three independent experiments.