PMID- 22236806
OWN - NLM
STAT- MEDLINE
DCOM- 20120510
LR  - 20220408
IS  - 0006-3002 (Print)
IS  - 0006-3002 (Linking)
VI  - 1817
IP  - 4
DP  - 2012 Apr
TI  - Structural studies on bovine heart cytochrome c oxidase.
PG  - 579-89
LID - 10.1016/j.bbabio.2011.12.012 [doi]
AB  - Among the X-ray structures of bovine heart cytochrome c oxidase (CcO), reported 
      thus far, the highest resolution is 1.8A. CcO includes 13 different protein 
      subunits, 7 species of phospholipids, 7 species of triglycerides, 4 redox-active 
      metal sites (Cu(A), heme a (Fe(a)), Cu(B), heme a(3) (Fe(a3))) and 3 
      redox-inactive metal sites (Mg(2+), Zn(2+) and Na(+)). The effects of various 
      O(2) analogs on the X-ray structure suggest that O(2) molecules are transiently 
      trapped at the Cu(B) site before binding to Fe(a3)(2+) to provide O(2)(-). This 
      provides three possible electron transfer pathways from Cu(B), Fe(a3) and Tyr244 
      via a water molecule. These pathways facilitate non-sequential 3 electron 
      reduction of the bound O(2)(-) to break the OO bond without releasing active 
      oxygen species. Bovine heart CcO has a proton conducting pathway that includes a 
      hydrogen-bond network and a water-channel which, in tandem, connect the positive 
      side phase with the negative side phase. The hydrogen-bond network forms two 
      additional hydrogen-bonds with the formyl and propionate groups of heme a. Thus, 
      upon oxidation of heme a, the positive charge created on Fe(a) is readily 
      delocalized to the heme peripheral groups to drive proton-transport through the 
      hydrogen-bond network. A peptide bond in the hydrogen-bond network and a 
      redox-coupled conformational change in the water channel are expected to 
      effectively block reverse proton transfer through the H-pathway. These functions 
      of the pathway have been confirmed by site-directed mutagenesis of bovine CcO 
      expressed in HeLa cells.
CI  - Copyright A(c) 2011. Published by Elsevier B.V.
FAU - Yoshikawa, Shinya
AU  - Yoshikawa S
AD  - Department of Life Science, University of Hyogo, Hyogo, Japan. 
      yoshi@sci.u-hyogo.ac.jp
FAU - Muramoto, Kazumasa
AU  - Muramoto K
FAU - Shinzawa-Itoh, Kyoko
AU  - Shinzawa-Itoh K
FAU - Mochizuki, Masao
AU  - Mochizuki M
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Review
DEP - 20120104
PL  - Netherlands
TA  - Biochim Biophys Acta
JT  - Biochimica et biophysica acta
JID - 0217513
RN  - 0 (Lipids)
RN  - 0 (Metals)
RN  - 0 (Protein Subunits)
RN  - 42VZT0U6YR (Heme)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
RN  - S88TT14065 (Oxygen)
SB  - IM
MH  - Animals
MH  - Binding Sites
MH  - Cattle
MH  - Crystallography, X-Ray
MH  - Electron Transport Complex IV/*chemistry/metabolism
MH  - Heme/chemistry/metabolism
MH  - Lipids/chemistry
MH  - Metals/chemistry/metabolism
MH  - Myocardium/*enzymology
MH  - Oxidation-Reduction
MH  - Oxygen/chemistry/metabolism
MH  - Protein Binding
MH  - *Protein Conformation
MH  - Protein Subunits/chemistry/metabolism
EDAT- 2012/01/13 06:00
MHDA- 2012/05/11 06:00
CRDT- 2012/01/13 06:00
PHST- 2011/09/29 00:00 [received]
PHST- 2011/12/16 00:00 [revised]
PHST- 2011/12/29 00:00 [accepted]
PHST- 2012/01/13 06:00 [entrez]
PHST- 2012/01/13 06:00 [pubmed]
PHST- 2012/05/11 06:00 [medline]
AID - S0005-2728(12)00002-3 [pii]
AID - 10.1016/j.bbabio.2011.12.012 [doi]
PST - ppublish
SO  - Biochim Biophys Acta. 2012 Apr;1817(4):579-89. doi: 10.1016/j.bbabio.2011.12.012. 
      Epub 2012 Jan 4.