Extended Data Fig. 2: Comparison of chemotactic ability of V. cholerae wild-type and ΔbsrV strains.
From: d-amino acids signal a stress-dependent run-away response in Vibrio cholerae
a, Chemotactic ability of ΔbsrV mutant. Both chemotactic bias and swimming speed were analysed in presence of several known chemoeffectors to compare the behaviour of wild-type (wt) and ΔbsrV mutant cells. Chemotaxis was measured in microfluidic devices, monitoring cell motion from a reservoir filled with cells in motility buffer to a reservoir filled only with 100 µM of indicated compound in motility buffer. Blank, no attractant in second reservoir; L-Arg, L-arginine; AiBu, α-aminoisobutiric acid; GABA, γ-aminobutyric acid; Succ, succinate. Each data point represents the average over the 3 time points for a given experiment (n = 4) and the line represents the mean. Significant differences (unpaired t-test) are indicated by *** (p < 0.001) and was evaluated relative to the blank for the given strains. b, Swimming speed analysis of V. cholerae grown in presence of D-Arg. Cells were grown in TB (± 500 μM D-Arg) and transferred to fresh TB for swimming speed measurements. Each point represents the mean and error bars indicate the SD over 3 biological replicates. c, Motility analysis of non-chemotactic V. cholerae cells in presence and absence of D-Arg. Relative motility on soft-agar plates supplemented or not with 5 mM D-Arg of several strains compared to wild-type (wt). ΔbsrV and ΔcheY3 strains are included as controls. Error bars in c represent mean values ± SD of 3 biologically independent replicates. Significant differences (unpaired t-test, adjusted for multiple comparison using Bonferroni-Dunn method) are indicated by *** (p < 0.001). See source data.
