FIG. 4.

Induction of scpB reporter gene activity in strain O90RΔrgfC, which harbors a deletion of the rgfC histidine kinase, following culture in THY medium supplemented with different serum stimuli. The amount of serum supplementation is indicated. Shown are mean values above baseline (controls were set to 1) and standard deviations from three independent experiments. HS, pooled human serum; iHS, heat-inactivated pooled human serum; FCS, fetal calf serum; iFCS, heat-inactivated fetal calf serum.