Fig. 3

Rsp activation of the cnt operon can act independently of the repressors Fur and Zur. Relative expression of cntK, cntA and cntE genes in the fur, zur single mutants and fur rsp, zur rsp double mutants relative to USA300 JE2 strain in rich media (TSB) were assessed by RT-qPCR. The bars represent the means of relative expression from at least three independent experiments. The error bars show standard errors of the means. Statistical differences were determined by Mann-Whitney U Test except for the comparisons of the parental strain vs the fur mutant and the parental strain vs the zur mutant in which a unpaired Student’s t-test was performed (*P < 0.05)