title: Yeast Cox11, a protein essential for cytochrome c oxidase assembly, is a Cu(I)-binding protein.
abstract: Cox11 is a protein essential for respiratory growth and has been implicated in the assembly of the Cu(B) site of cytochrome c oxidase. In the present study, we demonstrate that Cox11 is a copper-binding protein. The soluble C-terminal domain of Cox11 forms a dimer that coordinates one Cu(I) per monomer via three thiolate ligands. The two Cu(I) ions in the dimer exist in a binuclear cluster and appear to be ligated by three conserved Cys residues. Mutation of any of these Cys residues reduces Cu(I) binding and confers respiratory incompetence. Cytochrome c oxidase activity is reduced in these mutants. Thus, the residues important for Cu(I) binding correlate with in vivo function, suggesting that Cu(I) binding is important in Cox11 function.
authors.affiliation: University of Utah Health Sciences Center, Salt Lake City, UT 84132, USA.
authors.forename: Heather S
authors.initials: HS
authors.lastname: Carr
authors.forename: Graham N
authors.initials: GN
authors.lastname: George
authors.forename: Dennis R
authors.initials: DR
authors.lastname: Winge
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry*; D003300:Copper / Q000378:metabolism; D003545:Cysteine / Q000378:metabolism; D019281:Dimerization; D003576:Electron Transport Complex IV / Q000737:chemistry* / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D011487:Protein Conformation; D029701:Saccharomyces cerevisiae Proteins
chemical_list: C086106:COX11 protein, S cerevisiae; D002352:Carrier Proteins; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins; C023548:copper-binding protein; D003300:Copper; D003576:Electron Transport Complex IV; D003545:Cysteine