FIG 5.

HilD and SlyA act additively as anti-H-NS factors, whereas OmpR acts independently of H-NS, to induce expression of ssrAB during growth in LB. Expression of the ssrAB-cat−302/+478 (A) and ssrAB-cat+10 (B) transcriptional fusions carried by the pssrAB-cat-302/+478 and pssrAB-cat+10 plasmids, respectively, was tested in WT S. Typhimurium strain and its isogenic ΔompR, ΔhilD, ΔslyA, ΔhilD ΔslyA, ΔssrB, and ΔphoP mutants. CAT-specific activity was determined from samples of bacterial cultures grown for 9 h in LB at 37°C. Data represent the mean with standard deviation of the results from three independent experiments performed in duplicate. Statistically different values are indicated (***, P < 0.001; ****, P < 0.0001).