Representative swarming plates showing wild-type, ΔcetA, ΔcetB, ΔcetAB and ΔflaAB strains after 24 hours incubation at 37°C in microaerobic conditions in: A) Brucella (0.4% agar, 0.01% TTC) and B) DMEM supplemented with 5% MEMα (0.4% agar, 0.01% TTC). C) Representative composite image of parallel TTC- and resazurin-based tube assays. Brucella soft agar was supplemented with either 0.01% TTC (T) or 0.0001% resazurin (R) and were incubated after inoculation at the top at 37°C in air and photographs taken at the times indicated. Asterisks are used to show the edge of the dye front. D) DMEM/MEMα swarming assay showing halo formation of the wild-type, ΔcheA, ΔcetZ, and ΔcetZ::cetZ* strains. E) Representative tube assay after 40 hrs incubation in air (37°C) showing migration of wild-type, ΔcetA, ΔcetB, ΔcetAB, ΔcetZ (cj1110c), ΔcetA ΔcetZ, ΔcetB ΔcetZ, and ΔcetAB ΔcetZ strains. Asterisks are used to show the edge of the dye front.