This bacterial enzyme is present in pathogenic Salmonella species, uropathogenic and avian pathogenic Escherichia coli strains, and certain Klebsiella strains. Unlike EC 3.1.1.108, iron(III)-enterobactin esterase, which acts only on enterobactin, this enzyme can also act on the C-glucosylated forms known as salmochelins. Unlike EC 3.1.1.109, iron(III)-salmochelin esterase (IroD), IroE prefers apo siderophores as substrates, and is assumed to act before the siderophores are exported out of the cell. It hydrolyses the trilactone only once, producing linearized trimers.