Fig. 3

c-di-GMP inhibition of gbpA expression is influenced by carbon source availability. V. cholerae strains containing the P _gbpA -Vc1-lacZ reporter fusion, with wild type c-di-GMP (vector, black bars) or reduced c-di-GMP (pPDE, grey bars), were grown in M9 minimal medium with 0.5 % (w/v) N-acetylglucosamine (GlcNAc), glucose, maltose, sucrose, fructose or casamino acids at 37 °C with aeration to mid-logarithmic phase. PDE gene expression was induced as described in the Methods. Transcription was measured using β-galactosidase assays. Shown are the means and standard deviations from at least three independent experiments. For the indicated comparisons, ***P < 0.001 by unpaired t-test