Structures of Metal Sites of Oxidized Bovine Heart Cytochrome c Oxidase at 2.8 Å

DOI Web Site 被引用文献108件
  • Tomitake Tsukihara
    Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita 565, Japan.
  • Hiroshi Aoyama
    Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita 565, Japan.
  • Eiki Yamashita
    Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita 565, Japan.
  • Takashi Tomizaki
    Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita 565, Japan.
  • Hiroshi Yamaguchi
    Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita 565, Japan.
  • Kyoko Shinzawa-Itoh
    Department of Life Science, Himeji Institute of Technology, Karigohri Akoh, Hyogo 678-12, Japan.
  • Ryosuke Nakashima
    Department of Life Science, Himeji Institute of Technology, Karigohri Akoh, Hyogo 678-12, Japan.
  • Rieko Yaono
    Department of Life Science, Himeji Institute of Technology, Karigohri Akoh, Hyogo 678-12, Japan.
  • Shinya Yoshikawa
    Department of Life Science, Himeji Institute of Technology, Karigohri Akoh, Hyogo 678-12, Japan.

抄録

<jats:p> The high resolution three-dimensional x-ray structure of the metal sites of bovine heart cytochrome c oxidase is reported. Cytochrome c oxidase is the largest membrane protein yet crystallized and analyzed at atomic resolution. Electron density distribution of the oxidized bovine cytochrome c oxidase at 2.8 Å resolution indicates a dinuclear copper center with an unexpected structure similar to a [2Fe-2S]-type iron-sulfur center. Previously predicted zinc and magnesium sites have been located, the former bound by a nuclear encoded subunit on the matrix side of the membrane, and the latter situated between heme a <jats:sub>3</jats:sub> and Cu <jats:sub>A</jats:sub> , at the interface of subunits I and II. The O <jats:sub>2</jats:sub> binding site contains heme a <jats:sub>3</jats:sub> iron and copper atoms (Cu <jats:sub>B</jats:sub> ) with an interatomic distance of 4.5 Å; there is no detectable bridging ligand between iron and copper atoms in spite of a strong antiferromagnetic coupling between them. A hydrogen bond is present between a hydroxyl group of the hydroxyfarnesylethyl side chain of heme a <jats:sub>3</jats:sub> and an OH of a tyrosine. The tyrosine phenol plane is immediately adjacent and perpendicular to an imidazole group bonded to Cu <jats:sub>B</jats:sub> , suggesting a possible role in intramolecular electron transfer or conformational control, the latter of which could induce the redox-coupled proton pumping. A phenyl group located halfway between a pyrrole plane of the heme a <jats:sub>3</jats:sub> and an imidazole plane liganded to the other heme (heme a) could also influence electron transfer or conformational control. </jats:p>

収録刊行物

  • Science

    Science 269 (5227), 1069-1074, 1995-08-25

    American Association for the Advancement of Science (AAAS)

被引用文献 (108)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ