Figure 5.

Explorers’ are hyperflagellated.A. Real-time PCR. Increase of flagella gene expression is in correlation to kanamycin concentrations. Explorers were isolated after pre-exposure to 10 (white), 20 (light grey) and 40 μg ml⁻¹ (dark grey) kanamycin for 18 h, and examined relatively to the mixed culture. Y-axis represents the binary logarithm of genes relative expression (ΔΔCt). X-axis: sigD, fliI, flgK, motA and flagellin (hag).B. Western blot with anti-flagellin antibody. Elevation of flagellin in explorers isolated from either 40 μg ml⁻¹ kanamycin (Kan t) or 15.6 μg ml⁻¹ – chloramphenicol (Cl t). Non-treated bacteria (Cl c, Kan c). The number of cells in all samples (10¹⁰ CFU/ml) was equalized; thus, the levels of proteins presented here are per cell.C. TEM imaging. Increase of flagella filaments in explorers in comparison to builders. Scale bar = 2 μm.D. In the presence of Congo red, flagella production is inhibited. Mixed culture and explorers were plated on agar plates with 20 μg ml⁻¹ kanamycin (I and II) and 20 μg ml⁻¹ kanamycin + 400 μg ml⁻¹ Congo red (III and IV) and incubated for 24 h. Absence of flagella in the presence of Congo red prevented swarming of the mixed as well as explorers colonies. Scale bar = 5 mm.