title: The copper transporter (Ctr) family of Cu+ uptake systems.
abstract: Copper (Cu(+)) transporters of the Ctr family are sequence diverse eukaryotic proteins that function by an unknown mechanism of action. We have conducted bioinformatic analyses of sequenced Ctr proteins. Multiple paralogues are found in single organisms, and these may be either closely or distantly related to each other. Protein phylogeny generally correlates with organismal source and protein size with proteins of each cluster being derived from a specific eukaryotic kingdom and exhibiting characteristic domain arrangements. Some homologues exhibit repeats of the basic 3 TMS unit. Regions of conserved hydrophobicity and amphipathicity suggest functional roles, particularly for putative TMSs 2 and 3 which possess a nearly fully conserved M X(3) M motif in putative TMS2. We propose that this motif comprises the transmembrane Cu(+)-binding site in oligomeric channels that take up Cu(+) by a passive, membrane potential-dependent mechanism.
authors.affiliation: Division of Biological Sciences, University of California at San Diego, La Jolla 92093-0116, USA.
authors.forename: Quentin C
authors.initials: QC
authors.lastname: Dumay
authors.forename: Aurore J
authors.initials: AJ
authors.lastname: Debut
authors.forename: Nahla M
authors.initials: NM
authors.lastname: Mansour
authors.forename: Milton H
authors.initials: MH
authors.lastname: Saier
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism*; D003300:Copper / Q000378:metabolism*; D019143:Evolution, Molecular; D005656:Fungal Proteins / Q000235:genetics / 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; D003300:Copper