PMID- 17662458
OWN - NLM
STAT- MEDLINE
DCOM- 20080115
LR  - 20131121
IS  - 0162-0134 (Print)
IS  - 0162-0134 (Linking)
VI  - 101
IP  - 10
DP  - 2007 Oct
TI  - Theoretical study on electronic structures of FeOO, FeOOH, FeO(H2O), and FeO in 
      hemes: as intermediate models of dioxygen reduction in cytochrome c oxidase.
PG  - 1410-27
AB  - The electronic structures of heme-dioxygen complexes have been studied as 
      intermediate models of dioxygen reduction mechanism catalyzed by the mixed 
      valence (MV) and fully reduced (FR) cytochrome c oxidase (CcO). Dioxygen, protons 
      and electrons were sequentially added to the heme along the proposed reaction 
      path for the O(2) reduction mechanism. The electronic structures of [FeOO], 
      [FeOO](-), [FeOOH](+), [FeOOH], [Fe=O, H(2)O](+), [Fe=O](+) and [Fe=O] were 
      thoroughly investigated by using the unrestricted hybrid exchange-correlation 
      functional B3LYP method. The additions of two protons and an electron to [FeOO] 
      lead to the OO bond cleavage to produce a H(2)O molecule with the electron 
      transfer from Fe(II) in heme to the OO moiety. It is shown that the intrinsic OO 
      bond cleavage occurs by adding two protons and two electrons into the OO bond, 
      indicating consistency with a H(2)O formation catalyzed by both MV and FR CcO. 
      The study of the electronic structures of heme-dioxygen complexes gave the 
      different proposals for the mechanisms of a H(2)O formation by both MV and FR 
      CcO. For the mixed valence CcO, starting from the [FeOO] complex, the final 
      products are single H(2)O molecule and compound I of the oxo heme. For the fully 
      reduced CcO, the final products are single H(2)O molecule and compound II of the 
      oxo heme which is a reduced state of the compound I.
FAU - Yoshioka, Yasunori
AU  - Yoshioka Y
AD  - Department of Chemistry for Materials, Graduate School of Engineering, Mie 
      University, Kurima-machiya 1577, Tsu, Mie 514-8507, Japan. 
      yyoshi@chem.mie-u.ac.jp
FAU - Satoh, Hiroyuki
AU  - Satoh H
FAU - Mitani, Masaki
AU  - Mitani M
LA  - eng
PT  - Journal Article
DEP - 20070621
PL  - United States
TA  - J Inorg Biochem
JT  - Journal of inorganic biochemistry
JID - 7905788
RN  - 0 (Iron Compounds)
RN  - 42VZT0U6YR (Heme)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
RN  - S88TT14065 (Oxygen)
SB  - IM
MH  - Electron Transport Complex IV/*chemistry
MH  - Electrons
MH  - Heme/*chemistry
MH  - Iron Compounds/*chemistry
MH  - *Models, Chemical
MH  - Molecular Structure
MH  - Oxidation-Reduction
MH  - Oxygen/*chemistry
EDAT- 2007/07/31 09:00
MHDA- 2008/01/16 09:00
CRDT- 2007/07/31 09:00
PHST- 2007/01/10 00:00 [received]
PHST- 2007/05/14 00:00 [revised]
PHST- 2007/05/23 00:00 [accepted]
PHST- 2007/07/31 09:00 [pubmed]
PHST- 2008/01/16 09:00 [medline]
PHST- 2007/07/31 09:00 [entrez]
AID - S0162-0134(07)00121-3 [pii]
AID - 10.1016/j.jinorgbio.2007.05.018 [doi]
PST - ppublish
SO  - J Inorg Biochem. 2007 Oct;101(10):1410-27. doi: 10.1016/j.jinorgbio.2007.05.018. 
      Epub 2007 Jun 21.