PMID- 17530783
OWN - NLM
STAT- MEDLINE
DCOM- 20070801
LR  - 20181113
IS  - 0006-2960 (Print)
IS  - 1520-4995 (Electronic)
IS  - 0006-2960 (Linking)
VI  - 46
IP  - 24
DP  - 2007 Jun 19
TI  - Differential stability of dimeric and monomeric cytochrome c oxidase exposed to 
      elevated hydrostatic pressure.
PG  - 7146-52
AB  - Detergent-solubilized dimeric and monomeric cytochrome c oxidase (CcO) have 
      significantly different quaternary stability when exposed to 2-3 kbar of 
      hydrostatic pressure. Dimeric, dodecyl maltoside-solubilized cytochrome c oxidase 
      is very resistant to elevated hydrostatic pressure with almost no perturbation of 
      its quaternary structure or functional activity after release of pressure. In 
      contrast to the stability of dimeric CcO, 3 kbar of hydrostatic pressure triggers 
      multiple structural and functional alterations within monomeric cytochrome c 
      oxidase. The perturbations are either irreversible or slowly reversible since 
      they persist after the release of high pressure. Therefore, standard biochemical 
      analytical procedures could be used to quantify the pressure-induced changes 
      after the release of hydrostatic pressure. The electron transport activity of 
      monomeric cytochrome c oxidase decreases by as much as 60% after exposure to 3 
      kbar of hydrostatic pressure. The irreversible loss of activity occurs in a time- 
      and pressure-dependent manner. Coincident with the activity loss is a sequential 
      dissociation of four subunits as detected by sedimentation velocity, 
      high-performance ion-exchange chromatography, and reversed-phase and SDS-PAGE 
      subunit analysis. Subunits VIa and VIb are the first to dissociate followed by 
      subunits III and VIIa. Removal of subunits VIa and VIb prior to pressurization 
      makes the resulting 11-subunit form of CcO even more sensitive to elevated 
      hydrostatic pressure than monomeric CcO containing all 13 subunits. However, 
      dimeric CcO, in which the association of VIa and VIb is stabilized, is not 
      susceptible to pressure-induced inactivation. We conclude that dissociation of 
      subunit III and/or VIIa must be responsible for pressure-induced inactivation of 
      CcO since VIa and VIb can be removed from monomeric CcO without significant 
      activity loss. These results are the first to clearly demonstrate an important 
      structural role for the dimeric form of cytochrome c oxidase, i.e., stabilization 
      of its quaternary structure.
FAU - Stanicova, Jana
AU  - Stanicova J
AD  - Department of Biochemistry, The University of Texas Health Science Center, 7703 
      Floyd Curl Drive, San Antonio, Texas 78229-3900, USA.
FAU - Sedlak, Erik
AU  - Sedlak E
FAU - Musatov, Andrej
AU  - Musatov A
FAU - Robinson, Neal C
AU  - Robinson NC
LA  - eng
GR  - R01 GM024795/GM/NIGMS NIH HHS/United States
GR  - R01 GM024795-25/GM/NIGMS NIH HHS/United States
GR  - GMS 24795/PHS HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
DEP - 20070526
PL  - United States
TA  - Biochemistry
JT  - Biochemistry
JID - 0370623
RN  - 0 (Detergents)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
SB  - IM
MH  - Animals
MH  - Cattle
MH  - Chromatography, Ion Exchange
MH  - Detergents
MH  - Dimerization
MH  - Electron Transport
MH  - Electron Transport Complex IV/antagonists & inhibitors/*chemistry/metabolism
MH  - Enzyme Stability
MH  - Hydrostatic Pressure
MH  - In Vitro Techniques
MH  - Kinetics
MH  - Models, Molecular
MH  - Protein Structure, Quaternary
MH  - Solubility
PMC - PMC2561924
MID - NIHMS30545
EDAT- 2007/05/29 09:00
MHDA- 2007/08/02 09:00
PMCR- 2008/10/06
CRDT- 2007/05/29 09:00
PHST- 2007/05/29 09:00 [pubmed]
PHST- 2007/08/02 09:00 [medline]
PHST- 2007/05/29 09:00 [entrez]
PHST- 2008/10/06 00:00 [pmc-release]
AID - 10.1021/bi700548a [doi]
PST - ppublish
SO  - Biochemistry. 2007 Jun 19;46(24):7146-52. doi: 10.1021/bi700548a. Epub 2007 May 
      26.