title: Plasmon-waveguide resonance studies of ligand binding to integral proteins in membrane fragments derived from bacterial and mammalian cells.
abstract: A procedure has been developed for directly depositing membrane fragments derived from bacterial cells (chromatophores from Rhodopseudomonas sphaeroides) and mammalian cells (mu-opioid receptor- and MC4 receptor-transfected human embryonic kidney (HEK) cells and rat trigeminal ganglion cells) on the silica surface of a plasmon-waveguide resonance (PWR) spectrometer. Binding of ligands (cytochrome c(2) for the chromatophores, the peptide agonists DAMGO and melanotan-II that are specific for the mu-opioid and MC4 receptors, and two nonpeptide agonists that are specific for the CB1 receptor) to these membrane fragments has been observed and characterized with high sensitivity using PWR spectral shifts. The K(D) values obtained are in excellent agreement with conventional pharmacological assays and with prior PWR studies using purified receptors inserted into deposited lipid bilayer membranes. These studies provide a new tool for obtaining useful biological information about receptor-mediated processes in real biological membranes.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, AZ 85721, USA.
authors.forename: Zdzislaw
authors.initials: Z
authors.lastname: Salamon
authors.forename: John
authors.initials: J
authors.lastname: Fitch
authors.forename: Minying
authors.initials: M
authors.lastname: Cai
authors.forename: Suneeta
authors.initials: S
authors.lastname: Tumati
authors.forename: Edita
authors.initials: E
authors.lastname: Navratilova
authors.forename: Gordon
authors.initials: G
authors.lastname: Tollin
mesh_terms: D000818:Animals; D020130:Bacterial Chromatophores / Q000378:metabolism; D045362:Cytochromes c2 / Q000378:metabolism; D006801:Humans; D008024:Ligands; D008565:Membrane Proteins / Q000737:chemistry*; D051381:Rats; D017450:Receptors, Opioid, mu / Q000737:chemistry / Q000378:metabolism*; D012242:Rhodobacter sphaeroides / Q000378:metabolism; D020349:Surface Plasmon Resonance / Q000379:methods*; D014162:Transfection
chemical_list: D008024:Ligands; D008565:Membrane Proteins; D017450:Receptors, Opioid, mu; D045362:Cytochromes c2