Figure 6. Relative expression of wzz mRNA (A and B) and LPS analysis (C) of rcsB pmrA double mutant.

A,B. Total mRNA was harvested from cultures of SEΔrcsBΔpmrA double mutant and S. Enteritidis wild type #5694 grown in LB media (A) or grown in low Mg²⁺, low Mg²⁺+Fe³⁺ and high Mg²⁺ (B). The relative mRNA amount was determined by reverse transcription real-time quantitative PCR and related to mRNA levels in wild type strain (A) or in wild type strain grown in low Mg²⁺ (B), set as 1. Values are means ± SD of five independent mRNA extractions performed in triplicates. * significant difference p<0.01 with respect to wild type strain grown in the same media; † significant difference p<0.05 with respect to same strain grown in pmrA-inducing conditions (low Mg²⁺ and low Mg²⁺+Fe³⁺). C. Equal amount of LPS was loaded in each lane and analyzed by Tricine/SDS-PAGE on a 14% (w/v) acrylamide gel followed by silver staining. The concentration of LPS was determined by measuring KDO using the purpald assay.