Fig. 4: Transcriptional changes in iron-dependent regulation of enterobactin uptake genes.

a Schematic overview of ferrienterobactin uptake by TonB-mediated active transport via FepA in K. pneumoniae. b Schematic representation of regulatory elements in the fepA/fes region and positions of mutations (noted in dark red) relative to the index isolate. mRNA levels for mutants (mean of n = 3 biological replicates with 95% CI) are relative to the index isolate for the respective conditions. Comparison to the index isolate was done by unpaired t-test with Bonferroni corrections for five comparisons; two-tailed p-values exceeding significance (<0.05) are depicted above the columns. c Changes in fepA and fes mRNA levels in the index isolate under low and high iron conditions. mRNA levels (mean of n = 3 biological replicates with 95% CI) are relative to the housekeeping gene glnA and further normalized to M9/Chelex + FeSO₄. Comparison between different conditions for each gene was done by unpaired t-test with Bonferroni corrections for two comparisons; two-tailed p-values are depicted above the columns. Source data are provided as a Source Data file.