Fig. 4.
Reorientations in swimming direction are required for V. cholerae biofilm dispersal. (A) Representative 16 h images and quantitation of biofilm biomass over time measured by time-lapse microscopy for WT V. cholerae, the ΔcheY3 mutant, and the cheY3D16K,Y109W (cheY3*) mutant. (B) The corresponding PvpsL-lux output for WT and the ΔcheY3 strain over the growth curve. (C) Representative, randomly colored, single-cell locomotion trajectories for the strains in A. (D) Turning frequencies of the strains in A. (E) Measured swimming velocities of the strains in A. (F) Proposed model for the role of motility and reorientation in biofilm dispersal. (G) Quantitation of biofilm biomass over time for WT and the ΔcheY3 mutant following treatment with DMSO or the motility inhibitor phenamil supplied at 5 h postinoculation. For biofilm biomass assays, n = 3 biological replicates and n = 3 technical replicates, ± SD (shaded). For vpsL-lux measurements, n = 3 biological replicates, ± SD (shaded). For motility measurements, 45 to 125 individual cells of each strain were tracked. In D and E, unpaired t tests were performed for statistical analysis. *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001; n.s., P > 0.05.