Figure 3

A. InvE and IpaB expression in the hfq deletion mutant. Wild-type strain MS390 and the hfq mutant strain MS4831 were cultured in YENB media with or without NaCl, and then subjected to Western blot analysis. Strains and concentration of NaCl are indicated above the panels. Antibodies used in the experiment are indicated on the right side of the panels. B. Effect of ectopic Hfq expression on InvE and IpaB in the hfq mutant. hfq deletion mutants carrying an Hfq expression plasmid or a control plasmid were subjected to Western blot analysis. Strains were grown in YENB medium containing ampicillin and IPTG, or YENB medium containing ampicillin, IPTG and 150 mM NaCl at 37°C, and then harvested. Strains, concentration of NaCl and plasmids (minus, pTrc99A; plus, pTrc-hfq) are indicated above the panel. Lane 1, wild-type strain MS390 grown in YENB medium; Lane 2, Δhfq (pTrc99A) grown in YENB plus 0.1 mM IPTG; Lane 3, Δhfq (pTrc-hfq) grown in YENB plus 0.1 mM IPTG; Lane 4, Δhfq (pTrc99A) grown in YENB with 150 mM NaCl plus 1 mM IPTG; Lane 5, Δhfq (pTrc-hfq) grown in YENB with 150 mM NaCl plus 1 mM IPTG.