FIG 3.

β-Galactosidase assay of pfeT in different strain backgrounds. The pfeT-lacZ transcriptional fusion was monitored in WT, fur::kan, perR::tet, and fur::kan perR::tet strain backgrounds. Cells were grown in LB medium containing either no added iron or 300 μM iron (a concentration known to induce pfeT) to an OD₆₀₀ of 0.4. Data represent means ± standard deviations for at least three biological replicates. Significance was calculated using a two-way analysis of variance test with Šidák correction (**, P < 0.01; ****, P < 0.0001; ns, no statistical significance).