Fig. 5

Gene expression of sitA, iucA, and iutA in S. enterica strains grown under low-iron and high-iron conditions. Differential gene expression was examined in the S. enterica donor (SE163A), recipient (SE819), and transconjugant (SE819::IncFIB) strains using qRT-PCR and SYBR green assay. a relative gene expression of sitA; b relative gene expression of iucA; c relative gene expression of iutA, shown in a representative experiment. The error bars show the standard error of mean for two biological replicates (consisting of four technical replicates) of each strain. gmk was used as a reference gene to normalize the expression of target genes in different samples grown under low and high iron conditions. SE819 strain which does not possess IncFIB plasmid used as control to normalize the background gene expressions. Student’s t-test was performed to determine the statistically significant difference between two groups of samples. A p value ≤0.05 was considered a significant difference between the two groups compared, as indicated by the asterisks (ns = not significant)