FIG 5.

Osmotic stress response in V. harveyi. (A) Wild-type V. harveyi (BB120) cultures were grown in LOM with 1 mM choline (Ch.) containing 0.2 M, 0.3 M, 0.5 M, or 1 M NaCl. (B) Wild-type V. harveyi (BB120) cultures were grown in LOM containing 0.2 M NaCl in the presence or absence of 1 mM choline. At 6.5 h, either 1 M NaCl or 0.2 M NaCl (final concentrations) was added to the cultures (designated with the arrow specifying salt shock). In panels A and B, data show the mean and standard error from three biological replicates and represent those from three independent experiments. (C) V. harveyi strains were grown in LOM with 1 mM choline and 1 M NaCl. The strains tested were wild-type V. harveyi carrying a control plasmid (BB120::pLAFR2), V. harveyi ΔbetI carrying a control vector (JC2212::pLAFR2), and V. harveyi ΔbetI carrying a plasmid encoding betIBA-proXWV (JC2212::pJV302). The data shown are the means and standard errors from three biological replicates and represent those from three independent experiments. (D, E) The transcript levels of betIBA-proXWV (D) and Qrr4, luxR, and luxC (E) were assayed by qRT-PCR 15 min following salt shock. Test cultures of BB120 received salt shock with 1 M NaCl, and control cultures received an equal volume of 0.2 M NaCl (final concentrations). The data shown are the means and standard errors from three biological replicates and represent those from three independent experiments.