Table 2.

Biofilm formation and swarming motility of isolates with specific swimming and twitching phenotypes

	Swim-positive			Swim-negative
	Twitch-positive	Twitch-negative	Total	Twitch-positive	Twitch-negative	Total
Swarm-positive	106/154 (69 %)	26/40 (65 %)	132/199 (66 %)	10/20 (50 %)	1/8 (13 %)	11/28 (39 %)
Swarm diameter, median*	0.52	0.47	0.52	0.34	0.21	0.31
Biofilm, median (range)†	1.05 (0.4–2.2)	0.56 (0.2–3.8)	0.96 (0.2–3.8)	0.74 (0.1–2.8)	0.65 (0.2–2.6)	0.68 (0.1–2.8)

*The swarming colony diameter is normalized to the value obtained for PAO1. Swarm-negative isolates are excluded from the calculation of the median swarm diameter.

†Biofilm formation is normalized to a PAO1 control.