PMID- 24811894
OWN - NLM
STAT- MEDLINE
DCOM- 20140813
LR  - 20140616
IS  - 1096-0384 (Electronic)
IS  - 0003-9861 (Linking)
VI  - 554
DP  - 2014 Jul 15
TI  - Redox equilibration after one-electron reduction of cytochrome c oxidase: radical 
      formation and a possible hydrogen relay mechanism.
PG  - 36-43
LID - S0003-9861(14)00146-5 [pii]
LID - 10.1016/j.abb.2014.04.015 [doi]
AB  - Kinetic studies using UV/visible and EPR spectroscopy were carried out to follow 
      the distribution of electrons within beef heart cytochrome c oxidase (CcO), both 
      active and cyanide-inhibited, following addition of reduced cytochrome c as 
      electron donor. In the initial one-electron reduced state the electron is shared 
      between three redox centers, heme a, CuA and a third site, probably CuB. Using a 
      rapid freeze system and the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) a 
      protein radical was also detected. The EPR spectrum of the DMPO adduct of this 
      radical was consistent with tyrosyl radical capture. This may be a feature of a 
      charge relay mechanism involved in some part of the CcO electron transfer system 
      from bound cytochrome c via CuA and heme a to the a3CuB binuclear center.
CI  - Copyright (c) 2014 Elsevier Inc. All rights reserved.
FAU - Ashe, Damian
AU  - Ashe D
AD  - Biochemistry Unit, Department of Pre-Clinical Sciences, Faculty of Medical 
      Sciences, University of the West Indies, St. Augustine, Trinidad and Tobago.
FAU - Alleyne, Trevor
AU  - Alleyne T
AD  - Biochemistry Unit, Department of Pre-Clinical Sciences, Faculty of Medical 
      Sciences, University of the West Indies, St. Augustine, Trinidad and Tobago.
FAU - Wilson, Michael
AU  - Wilson M
AD  - Molecular Biophysics Research Group, School of Biological Sciences, University of 
      Essex, Colchester, Essex CO4 3SQ, UK.
FAU - Svistunenko, Dimitri
AU  - Svistunenko D
AD  - Molecular Biophysics Research Group, School of Biological Sciences, University of 
      Essex, Colchester, Essex CO4 3SQ, UK.
FAU - Nicholls, Peter
AU  - Nicholls P
AD  - Molecular Biophysics Research Group, School of Biological Sciences, University of 
      Essex, Colchester, Essex CO4 3SQ, UK. Electronic address: pnicholl@essex.ac.uk.
LA  - eng
PT  - Journal Article
DEP - 20140505
PL  - United States
TA  - Arch Biochem Biophys
JT  - Archives of biochemistry and biophysics
JID - 0372430
RN  - 0 (Cyclic N-Oxides)
RN  - 0 (Free Radicals)
RN  - 0 (Spin Labels)
RN  - 7170JZ1QF3 (5,5-dimethyl-1-pyrroline-1-oxide)
RN  - 7YNJ3PO35Z (Hydrogen)
RN  - 9007-43-6 (Cytochromes c)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
SB  - IM
MH  - Animals
MH  - Cattle
MH  - Cyclic N-Oxides
MH  - Cytochromes c/chemistry/metabolism
MH  - Electron Spin Resonance Spectroscopy
MH  - Electron Transport
MH  - Electron Transport Complex IV/*chemistry/*metabolism
MH  - Free Radicals/chemistry/metabolism
MH  - Horses
MH  - Hydrogen/metabolism
MH  - Kinetics
MH  - Models, Biological
MH  - Myocardium/enzymology
MH  - Oxidation-Reduction
MH  - Spectrophotometry
MH  - Spin Labels
OTO - NOTNLM
OT  - Amino acid radical
OT  - Cyanide
OT  - Cytochrome c oxidase
OT  - DMPO
OT  - Electron transfer
OT  - Spin trap
OT  - Tryptophan
OT  - Tyrosine
EDAT- 2014/05/09 06:00
MHDA- 2014/08/15 06:00
CRDT- 2014/05/10 06:00
PHST- 2014/02/20 00:00 [received]
PHST- 2014/04/09 00:00 [revised]
PHST- 2014/04/25 00:00 [accepted]
PHST- 2014/05/10 06:00 [entrez]
PHST- 2014/05/09 06:00 [pubmed]
PHST- 2014/08/15 06:00 [medline]
AID - S0003-9861(14)00146-5 [pii]
AID - 10.1016/j.abb.2014.04.015 [doi]
PST - ppublish
SO  - Arch Biochem Biophys. 2014 Jul 15;554:36-43. doi: 10.1016/j.abb.2014.04.015. Epub 
      2014 May 5.