title: Frictional drag and electrical manipulation of recombinant proteins in polymer-supported membranes.
abstract: We establish a lipid monolayer supported by a polymer interface that offers advantages over conventional solid-supported membranes for determining the frictional drag at the membrane-protein interface as well as for electric field manipulation of membrane-anchored proteins. Polymer-supported monolayers with functional lipid anchors allow for the specific docking of His-tagged green fluorescent protein variants (His-EGFP and His-DsRed tetramer) onto the membrane surface at a defined surface density. In the first part, we measure the lateral diffusion coefficients of lipids and proteins and calculate the frictional drag at the protein-membrane interface. The second part deals with the electric field-induced accumulation of recombinant proteins on a patterned surface. The mean drift velocity of proteins, which can be obtained analytically from the shape of the steady-state concentration gradient, can be controlled by tuning the interplay of electrophoresis and electroosmosis. The results demonstrate the potential of such molecular constructs for the local functionalization of solid substrates with membrane-associated proteins.
authors.affiliation: Department of Physics, Technical University of Munich, D-85748 Garching, Germany. tanaka@uni-heidelberg.de
authors.forename: Motomu
authors.initials: M
authors.lastname: Tanaka
authors.forename: Joachim
authors.initials: J
authors.lastname: Hermann
authors.forename: Ilka
authors.initials: I
authors.lastname: Haase
authors.forename: Markus
authors.initials: M
authors.lastname: Fischer
authors.forename: Steven G
authors.initials: SG
authors.lastname: Boxer
mesh_terms: D004586:Electrophoresis; D049452:Green Fluorescent Proteins / Q000737:chemistry*; D006639:Histidine / Q000737:chemistry; D008055:Lipids / Q000737:chemistry; D008565:Membrane Proteins / Q000737:chemistry; D008567:Membranes, Artificial; D008956:Models, Chemical; D009995:Osmosis; D011108:Polymers / Q000737:chemistry*; D011993:Recombinant Fusion Proteins / Q000737:chemistry*
chemical_list: D008055:Lipids; D008565:Membrane Proteins; D008567:Membranes, Artificial; D011108:Polymers; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; C033223:polyhistidine; D006639:Histidine