. 2001 Oct;69(10):6179–6185. doi: 10.1128/IAI.69.10.6179-6185.2001

TABLE 2.

Iron transport systems in E. coli CFT073 and its isogenic iron uptake mutants

Strain^a	FeSO₄ utilization^b	Hemin utilization^b	Aerobactin		Enterobactin
Strain^a	FeSO₄ utilization^b	Hemin utilization^b	Synthesis	Transport^b	Synthesis	Transport^b
CFT073	+	+	+	+	+	+
CFT073-TB	+	−	+	−	+	−
CFT073-TB(pYUK1)	+	+	+	+	+	+
CFT073-LH	+	−^c	+	+	+	+
CFT073-ENT	+	+	+	+	−	+
CFT073-IUC	+	+	−	+	+	+
CFT073-ENT/IUC	+	+	−	+	−	+
CFT073-IUT	+	+	+	−	+	+

Abbreviations: -TB, tonB; -LH, chuA; -ENT, entF; -IUC, iucB; -ENT/IUC, entF iucB; -IUT, iutA; pYUK1, TonB⁺ plasmid.

Bioassays were performed by seeding the strain in L-EDDA agar and spotting the indicated compound on the surface of the plate. + indicates a zone of growth around the iron compound. − indicates no stimulation of growth. Synthesis of siderophores was determined by chemical assays and bioassays.

A small amount of background growth was observed on occasion.