FIG. 1.

Kinetics of osmoregulated lacZ fusion expression in attached and free-living bacteria. Specific β-galactosidase activities of ompC-lacZ (A), proU-lacZ (B), fliC-lacZ (C), and wcaB-lacZ (D) fusions were measured in free-living (open squares) and sessile (filled squares) bacteria during biofilm development on petri dishes in M63-mannitol medium (A, B, and C) or on Plexiglas strips in M63-glucose medium (D) as described in Materials and Methods. Results are means ± standard deviations of 3 or 10 (∗) independent measurements.