FIG 4.

PAA degradation is important for the response to TMP/SMX. (A) Csu expression of Ab17978 WT, ΔpaaB, and paaB+ strains via anti-CsuA/B Western blot. The three strains were grown in LB or LB+TMP/SMX (3/15 μg/mL) for 4 h before whole cells were harvested and separated by SDS-PAGE. (B) Normalized intensity and quantification of panel A. Csu/RNAP intensity ratios were normalized to Csu/RNAP values in the WT strain grown in LB. (C) Csu expression of the WT and ΔpaaX strains when grown in LB. (D) Quantification of panel C. The intensity of Csu was normalized to RNAP. Points represent independent biological replicates, and significance was determined via Mann-Whitney U test (*, P < 0.05).