title: The iron/lead transporter superfamily of Fe/Pb2+ uptake systems.
abstract: Oxidase-dependent ferrous iron uptake transporters of the OFeT family and lead uptake transporters of the PbrT family comprise the iron/lead transporter (ILT) superfamily (transporter classification No. 9.A.10). All sequenced homologues of the ILT superfamily were multiply aligned, and conserved motifs, including fully conserved acidic residues in putative transmembrane segments (TMSs) 1 and 4, previously implicated in heavy metal binding, were identified. Topological analyses confirmed the presence of 7 conserved TMSs in a 3 + 3 + 1 arrangement where the two 3 TMS elements are internally repeated. Phylogenetic analyses revealed the presence of several sequence divergent clusters of orthologous proteins that group roughly according to the phylogenes of the organisms of origin. The results serve to characterize and provide evolutionary insight into a novel superfamily of heavy metal uptake transporters.
authors.affiliation: Division of Biological Sciences, University of California at San Diego, La Jolla 92093-0116, USA.
authors.forename: Aurore J
authors.initials: AJ
authors.lastname: Debut
authors.forename: Quentin C
authors.initials: QC
authors.lastname: Dumay
authors.forename: Ravi D
authors.initials: RD
authors.lastname: Barabote
authors.forename: Milton H
authors.initials: MH
authors.lastname: Saier
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism*; D017124:Conserved Sequence; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D007501:Iron / Q000378:metabolism*; D007854:Lead / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D019843:Archaeal Proteins; D001426:Bacterial Proteins; D027682:Cation Transport Proteins; D005656:Fungal Proteins; D007854:Lead; D007501:Iron