Part of a ferrous iron transporter composed of EfeU, EfeO and EfeB. However, this EfeUOB tripartite iron transporter is defective in E.coli strain K12 due to a frameshift mutation in EfeU. Belongs to the oxidase-dependent Fe transporter (OFeT) (TC 9.A.10.1) family. Could be the product of a pseudogene. Strain K12 contains a truncated, inactive permease due to a frameshift in position 34 that produces two separate ORFs. The sequence shown here is a reconstruction originating from EcoGene.