FIGURE 4.

Qrr-dependent regulation of virulence factor expression. A, expression levels of vvpE in various strains as measured by quantitative RT-PCR. RNA from wild type V. vulnificus, luxOD47E, ΔluxO, ΔsmcR, ΔluxOΔsmcR, Δqrr1–5, and ΔqrrΔsmcR was purified from cells at log phase (A₆₀₀ ∼0.6) and stationary phase (A₆₀₀ >2.0). RNA fold changes represent the vvpE expression level normalized to wild type. B, expression levels of vvhA in various strains as measured by quantitative RT-PCR. Values are averages from biological experiments done in triplicate. Error bars indicate the standard deviations.