Table 2.

Bacterial strains used in this study.

Strain (deleted gene)	Description
E. coli K-12 MG1655	Wild-type Escherichia coli laboratory strain
E. coli JW2142-1 (cir)	Unable to capture products of enterobactin hydrolysis
E. coli JW0790-2 (fiu)	Unable to capture products of enterobactin hydrolysis
E. coli JW1088-5 (fhuE)	Missing the outer-membrane coprogen receptor FhuE
E. coli JW0576-2 (fes)	Missing the Fes enzyme responsible for Fe(II) release from enterobactin
E. coli JW5086-3 (fepA)	Missing the outer-membrane enterobactin receptor FepA
E. coli JW0584-1 (fepB)	Missing the periplasmatic protein FepB involved in the transport of enterobactin and DHBS
E. coli JW0669-2 (fur)	Missing Fur - transcriptional repressor of genes responsible for siderophore receptor production
E. coli JW0146-2 (fhuA)	Missing the outer-membrane ferrichrome receptor FhuA
E. coli JW0148-1 (fhuD)	Missing the periplasmatic protein FhuD involved in the transport of ferrichrome, ferrioxamine, and coprogen