PMID- 16671753
OWN - NLM
STAT- MEDLINE
DCOM- 20070622
LR  - 20060504
IS  - 1520-6106 (Print)
IS  - 1520-5207 (Linking)
VI  - 110
IP  - 18
DP  - 2006 May 11
TI  - Orientational control of the physiological reaction of cytochrome c oxidase 
      tethered to a gold electrode.
PG  - 9339-47
AB  - The physiological reaction of a membrane protein is reconstituted on a 
      solid-supported electrode by orientational control via the position of an 
      affinity tag. Recombinant cytochrome c oxidase (CcO) from Rhodobacter sphaeroides 
      is immobilized on a chemically modified gold surface via the affinity of a 
      histidine tag (His-tag) to a nickel chelating nitrilotriacetic acid surface. 
      Control of the orientation is achieved by the adsorption of CcO through the 
      His-tag engineered into the two opposite sites of the membrane protein surface. 
      After reconstitution into a lipid layer, the functionality of this enzyme film 
      electrode is probed by surface-enhanced infrared absorption spectroscopy and 
      cyclic voltammetry. We demonstrate that cytochrome c (Cc) binds and initiates the 
      catalytic reaction of CcO only when the latter is orientated with subunit II 
      facing the bulk aqueous phase while Cc does not interact with the oppositely 
      orientated CcO. We infer from the observed catalytic dioxygen reduction at 
      potentials below 240 mV (vs a normal hydrogen electrode) that reduced Cc mediates 
      electron input into CcO in a way similar to the physiological pathway. The 
      quantitative analysis of the IR spectra indicates the presence of an inactive 
      population of Cc bound to CcO at equal amounts as the redox-active population. 
      This methodological approach demonstrates that the orientation of the membrane 
      protein can be controlled depending on the position of the affinity tag. The 
      approach is considered to be of general applicability as the introduction of 
      affinity tags is routine in current biochemistry.
FAU - Ataka, Kenichi
AU  - Ataka K
AD  - Forschungszentrum Julich, IBI-2: Structural Biology, 52425 Julich, Germany.
FAU - Richter, Bjorn
AU  - Richter B
FAU - Heberle, Joachim
AU  - Heberle J
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Phys Chem B
JT  - The journal of physical chemistry. B
JID - 101157530
RN  - 0 (Enzymes, Immobilized)
RN  - 0 (Membranes, Artificial)
RN  - 0 (Recombinant Proteins)
RN  - 7440-57-5 (Gold)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
SB  - IM
MH  - Adsorption
MH  - Electrochemistry
MH  - Electrodes
MH  - Electron Transport Complex IV/*chemistry/isolation & purification/*physiology
MH  - Enzymes, Immobilized/*chemistry
MH  - Gold/*chemistry
MH  - Kinetics
MH  - Membranes, Artificial
MH  - Models, Molecular
MH  - Recombinant Proteins/*chemistry
MH  - Rhodobacter sphaeroides/chemistry
MH  - Spectroscopy, Fourier Transform Infrared
MH  - Surface Properties
EDAT- 2006/05/05 09:00
MHDA- 2007/06/23 09:00
CRDT- 2006/05/05 09:00
PHST- 2006/05/05 09:00 [pubmed]
PHST- 2007/06/23 09:00 [medline]
PHST- 2006/05/05 09:00 [entrez]
AID - 10.1021/jp0534131 [doi]
PST - ppublish
SO  - J Phys Chem B. 2006 May 11;110(18):9339-47. doi: 10.1021/jp0534131.