title: pH and Potential Transients of the bc1Complex Co-Reconstituted in Proteo-Lipobeads with the Reaction Center from Rb. sphaeroides.
abstract: His-tag technology is employed to bind membrane proteins, such as the bc1complex and the reaction center (RC) from Rhodobacter sphaeroides, to spherical as well as planar surfaces in a strict orientation. Subsequently, the spherical and planar surfaces are subjected to in situ dialysis to form proteo-lipobeads (PLBs) and protein-tethered bilayer membranes, respectively. PLBs based on Ni-nitrileotriacetic acid-functionalized agarose beads that have diameters ranging from 50 to 150 μm are used to assess proton release and membrane potential parameters by confocal laser-scanning microscopy. The pH and potential transients are thus obtained from bc1activated by the RC. To assess the turnover of bc1excited by the RC in a similar setting, we used the planar surface of an attenuated total reflection crystal modified with a thin gold layer to carry out time-resolved surface-enhanced IR absorption spectroscopy triggered by flash lamp excitation. The experiments suggest that both proteins interact in a cyclic manner in both environments. The activity of the proteins seems to be preserved in the same manner as that in chromatophores or reconstituted in liposomes.
authors.affiliation: Biosensor Technologies, Austrian Institute of Technology GmbH, AIT , Donau-City Street 1, 1220 Vienna, Austria.|University of Natural Resources and Life Sciences , Gregor-Mendel-Straße 33, 1180 Wien, Austria.
authors.forename: Andreas F
authors.initials: AF
authors.lastname: Geiss
authors.affiliation: Indian Institute of Technology Kanpur , Kalyanpur, Kanpur, Uttar Pradesh 208016, India.
authors.forename: Raghav
authors.initials: R
authors.lastname: Khandelwal
authors.affiliation: Faculty of Chemistry, Department of Physical Chemistry, University of Vienna , Währinger Straße 42, 1090 Vienna, Austria.
authors.forename: Dieter
authors.initials: D
authors.lastname: Baurecht
authors.affiliation: Biosensor Technologies, Austrian Institute of Technology GmbH, AIT , Donau-City Street 1, 1220 Vienna, Austria.|Center of Electrochemical Surface Technology, CEST , Viktor-Kaplan-Str. 2, 2700 Wiener Neustadt, Austria.
authors.forename: Christina
authors.initials: C
authors.lastname: Bliem
authors.affiliation: Biosensor Technologies, Austrian Institute of Technology GmbH, AIT , Donau-City Street 1, 1220 Vienna, Austria.|Center of Electrochemical Surface Technology, CEST , Viktor-Kaplan-Str. 2, 2700 Wiener Neustadt, Austria.
authors.forename: Ciril
authors.initials: C
authors.lastname: Reiner-Rozman
authors.affiliation: Single-Molecule Microscopy Group, Jena University Hospital , Nonnenplan 2-4, 07743 Jena, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Boersch
authors.affiliation: Computational Biochemistry Group, University of Bayreuth , Universitätsstraße 30, NWI, 95447 Bayreuth, Germany.
authors.forename: G Matthias
authors.initials: GM
authors.lastname: Ullmann
authors.affiliation: R. D. Berlin Center for Cell Analysis and Modeling, University of Connecticut Health Center , Farmington, Connecticut 06030, United States.
authors.forename: Leslie M
authors.initials: LM
authors.lastname: Loew
authors.affiliation: Biosensor Technologies, Austrian Institute of Technology GmbH, AIT , Donau-City Street 1, 1220 Vienna, Austria.
authors.forename: Renate L C
authors.identifier: 0000-0003-1975-4681
authors.initials: RL
authors.lastname: Naumann
mesh_terms: D014450:Electron Transport Complex III / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism; D010316:Particle Size; D012242:Rhodobacter sphaeroides / Q000737:chemistry / Q000378:metabolism*; D013499:Surface Properties
chemical_list: D008051:Lipid Bilayers; D008081:Liposomes; D014450:Electron Transport Complex III