title: Characterization and structure of a Zn2+ and [2Fe-2S]-containing copper chaperone from Archaeoglobus fulgidus.
abstract: Bacterial CopZ proteins deliver copper to P1B-type Cu+-ATPases that are homologous to the human Wilson and Menkes disease proteins. The genome of the hyperthermophile Archaeoglobus fulgidus encodes a putative CopZ copper chaperone that contains an unusual cysteine-rich N-terminal domain of 130 amino acids in addition to a C-terminal copper binding domain with a conserved CXXC motif. The N-terminal domain (CopZ-NT) is homologous to proteins found only in extremophiles and is the only such protein that is fused to a copper chaperone. Surprisingly, optical, electron paramagnetic resonance, and x-ray absorption spectroscopic data indicate the presence of a [2Fe-2S] cluster in CopZ-NT. The intact CopZ protein binds two copper ions, one in each domain. The 1.8 A resolution crystal structure of CopZ-NT reveals that the [2Fe-2S] cluster is housed within a novel fold and that the protein also binds a zinc ion at a four-cysteine site. CopZ can deliver Cu+ to the A. fulgidus CopA N-terminal metal binding domain and is capable of reducing Cu2+ to Cu+. This unique fusion of a redox-active domain with a CXXC-containing copper chaperone domain is relevant to the evolution of copper homeostatic mechanisms and suggests new models for copper trafficking.
authors.affiliation: Department of Biochemistry, Molecular Biology, and Cell Biology, Northwestern University, Evanston, Illinois 60208, USA.
authors.forename: Matthew H
authors.initials: MH
authors.lastname: Sazinsky
authors.forename: Benjamin
authors.initials: B
authors.lastname: LeMoine
authors.forename: Maria
authors.initials: M
authors.lastname: Orofino
authors.forename: Roman
authors.initials: R
authors.lastname: Davydov
authors.forename: Krisztina Z
authors.initials: KZ
authors.lastname: Bencze
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Stemmler
authors.forename: Brian M
authors.initials: BM
authors.lastname: Hoffman
authors.forename: José M
authors.initials: JM
authors.lastname: Argüello
authors.forename: Amy C
authors.initials: AC
authors.lastname: Rosenzweig
mesh_terms: D015502:Absorptiometry, Photon; D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020816:Amino Acid Motifs / Q000502:physiology; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D019611:Archaeoglobus fulgidus / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites / Q000502:physiology; D027682:Cation Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D000073840:Copper-Transporting ATPases; D003545:Cysteine / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004578:Electron Spin Resonance Spectroscopy; D017136:Ion Transport / Q000502:physiology; D007501:Iron / Q000737:chemistry / Q000378:metabolism; D008667:Metalloproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010084:Oxidation-Reduction; D011485:Protein Binding / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000502:physiology; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D015032:Zinc / Q000737:chemistry* / Q000378:metabolism
chemical_list: D019843:Archaeal Proteins; D027682:Cation Transport Proteins; D008667:Metalloproteins; D018832:Molecular Chaperones; D003300:Copper; D007501:Iron; D000251:Adenosine Triphosphatases; D000073840:Copper-Transporting ATPases; D015032:Zinc; D003545:Cysteine