Inhibiting high-affinity Fe uptake decreases the ability of the fur* allele to suppress the growth defect of the Δfpa::tetM mutant during Fe starvation. (A) Growth of the WT (JMB1100), Δfpa::tetM (JMB8689), Δfpa::tetM fur* (JMB10678), fhuC::Tn (JMB7525), Δfpa::tetM fhuC::Tn (JMB10721), and Δfpa::tetM fur* fhuC::Tn (JMB10722) strains with or without 700 µM DIP or 500 µM EDDHA. Overnight cultures were grown in TSB, serially diluted, and spot plated. Pictures of a representative experiment are displayed. (B) Streptonigrin sensitivity was monitored using top-agar TSA overlays enclosing the WT, fhuC::Tn,Δfpa::tetM fur* (JMB10638), and Δfpa::tetM fur* fhuC::Tn (JMB10722) strains. Five microliter of 2.5 mg mL−1 streptonigrin was spotted upon the overlays, and the area of growth inhibition was measured after 18 hours of growth. The bars represent the average of three biological replicates with SDs displayed. Student’s t-tests were performed on the data in panels C and D. * indicates P < 0.05.