FIG. 1.
Swarming motility on LB and B media. In qualitative plate images, colonized agar appears white and uncolonized agar appears black on LB and B media, as indicated. Swarming cells colonize a larger surface area than nonswarming cells. All strains are derivatives of strain 3610 unless otherwise indicated. Bar, 2 cm. (A) Quantitative swarm expansion assays on solid medium and growth in liquid medium of the indicated strains on LB medium (closed symbols) and on B medium (open symbols). To indicate variability in a particular experiment, we have reproduced the quantitative swarm expansion assay of strain 3610 on LB and B media with error bars in Fig. S5 in the supplemental material. (B) Quantitative swarm expansion assays on LB (closed symbols) and B (open symbols) media. The following strains were used: DS3337 (sfp), DS2415 (swrA), DS5106 (168 swrA+), DS5758 (168 sfp+), and DS5759 (168 swrA+ sfp+). In all assays, B medium was made according to reference 2 except for strain DS5759, for which B medium was supplemented with 780 μM threonine to compensate for thrC auxotrophy. (C) Swarm plates of the indicated strains on LB medium made with equal parts peptone instead of tryptone. (D) Quantitative swarm expansion assays of the indicated 3610-derived mutant strains on LB medium (closed symbols) and on B medium (open symbols). The following strains were used: DS72 (yvzB), DS2268 (epr), DS3903 (phrC), DS4978 (rapC), DS4979 (oppD), DS2509 (swrB), and DS3649 (degU). All points are averages for three replicates.