FIG. 6.

CsrA-dependent regulation of an hfq′-′lacZ translational fusion. Cells were harvested at various times throughout growth and assayed for β-galactosidase activity. Growth medium was LB (A and B) or LB supplemented with 1% glucose (C). Growth curves for each strain in panels A, B, and C were essentially identical. The time shown is hours of cell growth. These experiments were conducted at least three times with similar results. Results from representative experiments are shown. (A) β-Galactosidase activity was determined for PLB785 (wild type [WT]) and PLB786 (csrA::kan). Cell growth was measured in strain PLB785. (B) β-Galactosidase activity was determined for PLB793 (csrA::kan/pCRA16 [WT]) and PLB789 (csrA::kan/pBR322 [csrA]). Cell growth was measured in strain PLB789. (C) β-Galactosidase activity was determined for PLB785 (WT, WT fusion), PLB786 (csrA::kan [csrA, WT fusion]), PLB923 (WT with mutant hfq′-′lacZ fusion), and PLB924 (csrA::kan [csrA] with mutant hfq′-′lacZ fusion). Cell growth was measured in strain PLB785.