TABLE 3.

Effect of different metals on iron depletion of E. coli strains harboring multiple gene deletions^a

Strain	Genotype	Systems still functional	Growth yield in the presence of DIP andb:
			No metal	MgCl2	ZnCl2	MnCl2	FeCl3
GR499	ΔzupT::cat ΔmntH ΔfeoABC ΔentC	Fec	0.070 ± 0.01	0.09 ± 0.04	0.14 ± 0.02	0.64 ± 0.02	0.66 ± 0.08
GR507	ΔzupT::cat ΔfeoABC ΔentC	Fec, MntH	0.39 ± 0.01	0.31 ± 0.01	0.51 ± 0.09	0.69 ± 0.03	0.65 ± 0.01
GR489	ΔmntH::cat ΔfeoABC ΔentC	Fec, ZupT	0.45 ± 0.03	0.42 ± 0.01	0.42 ± 0.01	0.64 ± 0.01	0.69 ± 0.08
GR460	ΔfeoABC::cat ΔentC	Fec, ZupT, MntH	0.29 ± 0.02	0.29 ± 0.02	0.35 ± 0.04	0.52 ± 0.02	0.65 ± 0.09
GR536	ΔfecA-E::kan ΔzupT::cat	None	0.09 ± 0.01	0.08 ± 0.02	0.17 ± 0.02	0.71 ± 0.01	0.22 ± 0.03
	ΔmntH ΔfeoABC ΔentC
GR538	ΔfecA-E::kan ΔzupT::cat ΔfeoABC ΔentC	MntH	0.52 ± 0	0.51 ± 0.01	0.51 ± 0.04	0.71 ± 0.01	0.81 ± 0
GR537	ΔfecA-E::kan ΔmntH::cat ΔfeoABC ΔentC	ZupT	0.40 ± 0.2	0.42 ± 0.02	0.64 ± 0.01	0.76 ± 0.01	0.79 ± 0.02
GR539	ΔfecA-E::kan ΔfeoABC::cat ΔentC	ZupT, MntH	0.50 ± 0.02	0.51 ± 0.05	0.68 ± 0.04	0.75 ± 0.02	0.83 ± 0.01

^aOvernight cultures grown in Luria-Bertani broth were diluted 1:500 in minimal medium and grown overnight. Cells were diluted 1:500 in fresh minimal medium, and after 2 h, cells were diluted 1:500 into fresh medium with the indicated additives. The dry weight was determined after 16 h of incubation at 37°C with shaking. Experiments were performed independently in duplicate, and the average with deviation was calculated.

^bAll at a final concentration of 50 μM.