The Whole Structure of the 13-Subunit Oxidized Cytochrome c Oxidase at 2.8 Å

• DOI: 10.1126/science.272.5265.1136
• Publication Date: 2006-10-27T18:30:41Z
• Authors: Tomitake Tsukihara; Hiroshi Aoyama; Eiki Yamashita; Takashi Tomizaki; Hiroshi Yamaguchi; Kyoko Shinzawa-Itoh; Ryosuke Nakashima; Rieko Yaono; Shinya Yoshikawa
• Keywords: Imidazole; Heme A

The crystal structure of bovine heart cytochrome c oxidase at 2.8 Å resolution with an R value 19.9 percent reveals 13 subunits, each different from the other, five phosphatidyl ethanolamines, three glycerols and two cholates, hemes A, copper, one magnesium, zinc. Of 3606 amino acid residues in dimer, 3560 have been converged to a reasonable by refinement. A hydrogen-bonded system, including propionate heme (heme a), part peptide backbone, imidazole ligand Cu , could provide electron transfer pathway between a. Two possible proton pathways for pumping, spanning matrix cytosolic surfaces, were identified, hydrogen bonds, internal cavities likely contain water molecules, structures that form bonds small conformational change side chains. Possible channels chemical protons produce H 2 O, removing produced water, O respectively, identified.