Fig. 1.

Regulation of HA/protease production by c-di-GMP. (A) Production of HA/protease. Strain C7258, containing plasmids pAT1568 (VieA, EAL domain), pAT1615 [VieA(E170A), inactive EAL domain], and pAT1662 (VCA0956, GGDEF domain), was grown in TSB medium, and PDE or DGC expression was induced as described in Materials and Methods. Cultures were incubated for 16 h, and the production of HA/protease was determined. Each value represents the mean for three independent cultures. Error bars indicate standard deviations. **, P < 0.01. (B) Motility assay. Overnight cultures of C7258 transformants were stabbed into swarm agar with or without (control) l-arabinose, and the plates were incubated at 30°C. Each of the resulting swarm diameters is the mean for three independent cultures. Error bars indicate standard deviations (*, P < 0.05; **, P < 0.01 for comparison of induced versus control cultures).