Figure 1.

Swarming of wt and motility mutants in control unstressed (Left) and compressed plates (Right). Cells were inoculated with a micropippete tip and incubated for 3 days at 33°C. wt, DK1622 (A⁺S⁺); S⁻: DK10407 (A⁺S⁻); A⁻, ASX1(A⁻S⁺). Arrows near the top of the compressed plates indicate the swarms measured to obtain E for Fig. 3. The inserted tubes are visible at the top.