Heterologous promoter-transposase- lacZ translational fusion reporter assays in wt and hfq−strains. (A) Schematic of the IS50-lacZ translational fusion with IS50 transposase and lpp promoters. The IS50 translational fusion (TLF) is as described in Figure 3A. The lpp-IS50 TLF contains the lpp promoter (-35 and -10 elements) fused to the IS50 transposase gene such that only IS50 sequences at, and downstream of the T1 transcriptional start, are present. (B) β-galactosidase activity for isogenic strains (wt or hfq−) harboring the indicated TLF on a multicopy plasmid. For each fusion, the activity was normalized to that of the wt strain. The data sets shown were compiled from two independent experiments, respectively, with each experiment including at least three replicates. Mean and standard error values are shown.