PMID- 20385840
OWN - NLM
STAT- MEDLINE
DCOM- 20100602
LR  - 20240317
IS  - 1091-6490 (Electronic)
IS  - 0027-8424 (Print)
IS  - 0027-8424 (Linking)
VI  - 107
IP  - 17
DP  - 2010 Apr 27
TI  - Bovine cytochrome c oxidase structures enable O2 reduction with minimization of 
      reactive oxygens and provide a proton-pumping gate.
PG  - 7740-5
LID - 10.1073/pnas.0910410107 [doi]
AB  - The O(2) reduction site of cytochrome c oxidase (CcO), comprising iron (Fe(a3)) 
      and copper (Cu(B)) ions, is probed by x-ray structural analyses of CO, NO, and 
      CN(-) derivatives to investigate the mechanism of the complete reduction of O(2). 
      Formation of the derivative contributes to the trigonal planar coordination of 
      and displaces one of its three coordinated imidazole groups while a water 
      molecule becomes hydrogen bonded to both the CN(-) ligand and the hydroxyl group 
      of Tyr244. When O(2) is bound to Fe2+a3 , it is negatively polarized (O2- ), and 
      expected to induce the same structural change induced by CN(-). This structural 
      change allows to receive three electron equivalents nonsequentially from Cu1B+, 
      Fe3+a3, and Tyr-OH, providing complete reduction of O(2) with minimization of 
      production of active oxygen species. The proton-pumping pathway of bovine CcO 
      comprises a hydrogen-bond network and a water channel which extend to the 
      positive and negative side surfaces, respectively. Protons transferred through 
      the water channel are pumped through the hydrogen-bond network electrostatically 
      with positive charge created at the Fe(a) center by electron donation to the O(2) 
      reduction site. Binding of CO or NO to induces significant narrowing of a section 
      of the water channel near the hydrogen-bond network junction, which prevents 
      access of water molecules to the network. In a similar manner, O(2) binding to is 
      expected to prevent access of water molecules to the hydrogen-bond network. This 
      blocks proton back-leak from the network and provides an efficient gate for 
      proton-pumping.
FAU - Muramoto, Kazumasa
AU  - Muramoto K
AD  - Department of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigohri, Akoh, 
      Hyogo 678-1297, Japan.
FAU - Ohta, Kazuhiro
AU  - Ohta K
FAU - Shinzawa-Itoh, Kyoko
AU  - Shinzawa-Itoh K
FAU - Kanda, Katsumasa
AU  - Kanda K
FAU - Taniguchi, Maki
AU  - Taniguchi M
FAU - Nabekura, Hiroyuki
AU  - Nabekura H
FAU - Yamashita, Eiki
AU  - Yamashita E
FAU - Tsukihara, Tomitake
AU  - Tsukihara T
FAU - Yoshikawa, Shinya
AU  - Yoshikawa S
LA  - eng
SI  - PDB/3AG1
SI  - PDB/3AG2
SI  - PDB/3AG3
SI  - PDB/3AG4
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20100412
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (Reactive Oxygen Species)
RN  - 31C4KY9ESH (Nitric Oxide)
RN  - 789U1901C5 (Copper)
RN  - 7U1EE4V452 (Carbon Monoxide)
RN  - E1UOL152H7 (Iron)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
RN  - S88TT14065 (Oxygen)
SB  - IM
CIN - Proc Natl Acad Sci U S A. 2010 May 11;107(19):8505-6. PMID: 20457906
MH  - Animals
MH  - Carbon Monoxide/metabolism
MH  - Cattle
MH  - Cell Respiration
MH  - Copper/chemistry
MH  - Electron Transport Complex IV/*chemistry/metabolism
MH  - Iron/chemistry
MH  - *Models, Molecular
MH  - Molecular Structure
MH  - Nitric Oxide/metabolism
MH  - Oxidation-Reduction
MH  - Oxygen/chemistry/*metabolism
MH  - Reactive Oxygen Species/*metabolism
MH  - X-Ray Diffraction
PMC - PMC2867921
COIS- The authors declare no conflict of interest.
EDAT- 2010/04/14 06:00
MHDA- 2010/06/03 06:00
PMCR- 2010/10/27
CRDT- 2010/04/14 06:00
PHST- 2010/04/14 06:00 [entrez]
PHST- 2010/04/14 06:00 [pubmed]
PHST- 2010/06/03 06:00 [medline]
PHST- 2010/10/27 00:00 [pmc-release]
AID - 0910410107 [pii]
AID - 200910410 [pii]
AID - 10.1073/pnas.0910410107 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 2010 Apr 27;107(17):7740-5. doi: 
      10.1073/pnas.0910410107. Epub 2010 Apr 12.