title: Streptavidin binding to biotinylated lipid layers on solid supports. A neutron reflection and surface plasmon optical study.
abstract: Neutron reflection and surface plasmon optical experiments have been performed to evaluate structural data of the interfacial binding reaction between the protein streptavidin and a solid-supported lipid monolayer partly functionalized by biotin moieties. Since both experimental techniques operate in a total internal reflection geometry at a substrate/solution interface, identical sample architectures allow for a direct comparison between the results obtained with these two recently developed methods. It is found that a monomolecular layer of dipalmitoyllecithin doped with 5 mol% of a biotinylated-phosphatidylethanolamine shows a thickness of d1 approximately (3.4 +/- 0.5) nm. Binding of streptavidin to the biotin groups results in an overall layer thickness of d = (5.9 + 0.5) nm that demonstrates the formation of a well-ordered protein monolayer with the (biotin+spacer) units of the functionalized lipids being fully embedded into the binding pocket of the proteins. It is demonstrated by model calculations that a more detailed picture of the internal structure of this supramolecular assembly can only be obtained if one uses deuterated lipid molecules, thus generating a high contrast between individual layers.
authors: Max Planck Institut für Polymerforschung, Mainz, Germany.
authors: A
authors: A
authors: Schmidt
authors: J
authors: J
authors: Spinke
authors: T
authors: T
authors: Bayerl
authors: E
authors: E
authors: Sackmann
authors: W
authors: W
authors: Knoll
mesh_terms: D001426:Bacterial Proteins; D001665:Binding Sites; D055592:Biophysical Phenomena; D001703:Biophysics; D001710:Biotin; D008051:Lipid Bilayers / Q000737:chemistry*; D009502:Neutrons; D055095:Optics and Photonics; D013057:Spectrum Analysis / Q000379:methods; D019809:Streptavidin; D013499:Surface Properties
chemical_list: D001426:Bacterial Proteins; D008051:Lipid Bilayers; D001710:Biotin; D019809:Streptavidin