Fig. 11
The activated σE and RcsCDB systems can work independently to suppress bacterial motility. (a) The mRNA levels of the σE-regulated gene yiiS and the RcsCDB-regulated gene yjbE in the RS218 strain with an unactivated or activated RcsCDB system. Arabinose (0.2%) was used to induce the overexpression of RcsB encoded in pRcsB (Table 1). (b) The mRNA levels of yiiS and yjbE in the bacteria with an unactivated or activated σE system. (c) The mRNA levels of yiiS in WT-RS218, Δprc-RS218, and ΔrcsBΔprc-RS218. (d) The mRNA levels of yjbE in WT-RS218, Δprc-RS218, and ΔdegSΔprc-RS218. The mRNA level of each gene, which was determined by qPCR, in a strain was normalized to the ftsZ level and presented as a relative level compared to that in WT-RS218. The results were derived from experiments performed in triplicate and are shown as the means ± standard deviations. pRcsB, pBAD harboring the rcsB gene driven by the arabinose-inducible promoter on the plasmid