FIG. 5.

Comparison of nikA-lacZ expression in attached and free-living bacteria grown under standard conditions (A) or in anaerobiosis (B). Biofilm cultures were performed in M63-mannitol medium on petri dishes incubated in Generbox anaerobic jars (B) or not (A) for 23 and 45 h and specific β-galactosidase activities were measured in free-living (open bars) and sessile (hatched bars) bacteria as described in Materials and Methods. Results are means ± standard deviations of three independent measurements.