Fig 4.

Deletion of the cepR gene of B. multivorans ATCC 17616 impairs swimming motility but not siderophore biosynthesis. (A) Electrophoretic separation of PCR amplicons confirms the absence of the bceF gene (expected size 222 bp) or the cepR gene (expected size 270 bp) from the ATCC 17616 genome. (B) Assessment of the mucoid phenotype in the wild-type and ΔbceF mutant after growth at 37°C for 72 hours. (C) Siderophore production in MM-CAS medium after 72 hours at 37°C. (D) Swimming motility of the wild-type ATCC 17616 and ΔcepR mutant (images on the left) and its quantification (n = 12). Swimming plates were incubated for 24 hours at 37°C. The ΔcepR mutant differed significantly from the wild-type strain for swimming motility. ***P < 0.001 by Tukey’s honestly significant difference multiple-comparison test.