title: 2D-SEIRA spectroscopy to highlight conformational changes of the cytochrome c oxidase induced by direct electron transfer.
abstract: Potentiometric titrations of the cytochrome c oxidase (CcO) immobilized in a biomimetic membrane system were followed by two-dimensional surface-enhanced IR absorption spectroscopy (2D SEIRAS) in the ATR-mode. Direct electron transfer was employed to vary the redox state of the enzyme. The CcO was shown to undergo a conformational transition from a non-activated to an activated state after it was allowed to turnover in the presence of oxygen. Differences between the non-activated and activated state were revealed by 2D SEIRA spectra recorded as a function of potential. The activated state was characterized by a higher number of correlated transitions as well as a higher number of amino acids associated with electron transfer.
authors.affiliation: Austrian Institute of Technology GmbH, AIT, Donau-City Str. 1, 1220 Vienna, Austria. C.Nowak@ait.ac.at
authors.forename: Christoph
authors.initials: C
authors.lastname: Nowak
authors.forename: Thamara
authors.initials: T
authors.lastname: Laredo
authors.forename: Jens
authors.initials: J
authors.lastname: Gebert
authors.forename: Jacek
authors.initials: J
authors.lastname: Lipkowski
authors.forename: Robert B
authors.initials: RB
authors.lastname: Gennis
authors.forename: Shelagh
authors.initials: S
authors.lastname: Ferguson-Miller
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Knoll
authors.forename: Renate L C
authors.initials: RL
authors.lastname: Naumann
mesh_terms: D000596:Amino Acids / Q000737:chemistry / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D055664:Electrochemical Techniques / Q000379:methods*; D004579:Electron Transport; D003576:Electron Transport Complex IV / Q000737:chemistry* / Q000378:metabolism; D004789:Enzyme Activation; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D012242:Rhodobacter sphaeroides / Q000201:enzymology; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D021122:Protein Subunits; D003576:Electron Transport Complex IV; D010100:Oxygen