Motility of the Y. pseudotuberculosis Δhfq strain on semisolid agar. (a) Y. pseudotuberculosis wild-type, Δhfq, ΔflgE, Δhfq ΔflgE, and Δhfq+phfq strains were cultured on semisolid agar plates at 22°C or 37°C, and motility was monitored at 1 and 4 days postinoculation. Images are representative of several experiments. (b) qRT-PCR of flhC, flgA, and fliC transcripts. Bars represent the relative average fold change compared to wild type for each transcript of 3 independent experiments.