Figure 4.

IS5 insertion stimulates both promoter and operon activities. (A) Diagram showing IS5 insertion at the Pbgl reporter (IS5Pbgl-lacZ). An IS5 element in the reverse direction is located at -207.5 upstream of the bglG translation start site. The native bgl operon is unchanged. (B) Diagram showing IS5 insertion at the bgl operon reporter (IS5Pbgl-bglG-lacZ). IS5 orientation and location are the same as in Figure 4A. In both (A) and (B), the blue bars represent the Crp binding sites (O_Crp) while the red bars represent the proposed H-NS binding sites (O_HNS). (C) Effects of IS5 insertion on Pbgl activities. (D) Effects of IS5 insertion on bgl operon activities. In both (C) and (D), test strains were cultured in M63 with glycerol and salicin as carbon sources. Sample collections and β-galactosidase assays were carried out as in Figure 1.