title: Biomimetic Membranes for Multi-Redox Center Proteins.
abstract: His-tag technology was applied for biosensing purposes involving multi-redox center proteins (MRPs). An overview is presented on various surfaces ranging from flat to spherical and modified with linker molecules with nitrile-tri-acetic acid (NTA) terminal groups to bind his-tagged proteins in a strict orientation. The bound proteins are submitted to in situ dialysis in the presence of lipid micelles to form a so-called protein-tethered bilayer lipid membrane (ptBLM). MRPs, such as the cytochrome c oxidase (CcO) from R. sphaeroides and P. denitrificans, as well as photosynthetic reactions centers (RCs) from R. sphaeroides, were thus investigated. Electrochemical and surface-sensitive optical techniques, such as surface plasmon resonance, surface plasmon-enhanced fluorescence, surface-enhanced infrared absorption spectroscopy (SEIRAS) and surface-enhanced resonance Raman spectroscopy (SERRS), were employed in the case of the ptBLM structure on flat surfaces. Spherical particles ranging from µm size agarose gel beads to nm size nanoparticles modified in a similar fashion were called proteo-lipobeads (PLBs). The particles were investigated by laser-scanning confocal fluorescence microscopy (LSM) and UV/Vis spectroscopy. Electron and proton transfer through the proteins were demonstrated to take place, which was strongly affected by the membrane potential. MRPs can thus be used for biosensing purposes under quasi-physiological conditions.
authors.affiliation: Austrian Institute of Technology GmbH, AIT, Donau-City-Str. 1, 1220 Vienna, Austria. kontakt@rlc-naumann.eu.
authors.forename: Renate L C
authors.initials: RL
authors.lastname: Naumann
authors.affiliation: Austrian Institute of Technology GmbH, AIT, Donau-City-Str. 1, 1220 Vienna, Austria. andreas.geiss.fl@ait.ac.at.
authors.forename: Andreas F
authors.initials: AF
authors.lastname: Geiss
authors.affiliation: Austrian Institute of Technology GmbH, AIT, Donau-City-Str. 1, 1220 Vienna, Austria. christoph.steininger.fl@ait.ac.at.
authors.forename: Christoph
authors.initials: C
authors.lastname: Steininger
authors.affiliation: Austrian Institute of Technology GmbH, AIT, Donau-City-Str. 1, 1220 Vienna, Austria. Wolfgang.Knoll@ait.ac.at.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Knoll
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D032701:Biomimetics / Q000379:methods; D015374:Biosensing Techniques; D055664:Electrochemical Techniques; D003576:Electron Transport Complex IV / Q000737:chemistry*; D055767:Immobilized Proteins / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D010084:Oxidation-Reduction; D010231:Paracoccus denitrificans / Q000737:chemistry*; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry*; D012242:Rhodobacter sphaeroides / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013059:Spectrum Analysis, Raman; D020349:Surface Plasmon Resonance
chemical_list: D001426:Bacterial Proteins; D055767:Immobilized Proteins; D008051:Lipid Bilayers; D045322:Photosynthetic Reaction Center Complex Proteins; D003576:Electron Transport Complex IV
keywords: UV/Vis spectroscopy; cytochrome c oxidase; his-tag technology; laser-scanning confocal microscopy; multi-redox center proteins; photosynthetic reaction centers; protein-tethered bilayer lipid membrane; proteo-lipobeads; surface-enhanced infrared absorption spectroscopy; surface-enhanced resonance Raman spectroscopy