title: Lipid/polydiacetylene films for colorimetric protein surface-charge analysis.
abstract: The distribution and organization of charges on a protein surface are fundamental properties which affect protein functions and interactions. We demonstrate a new approach for protein surface-charge analysis through modulating protein interactions with chromatic lipid/polydiacetylene (PDA) films. We show that visible and easily quantifiable blue-red transitions, induced on the film surface through electrostatic interactions between the negatively charged PDA and positive soluble species, constitute an effective means for characterizing protein surface charge. Specifically, protein-film interactions can be significantly modulated by complexation between the tested macromolecules and lipid-embedded multivalent calixarene ligands displaying charged residues, making possible protein discrimination based upon the abundance and organization of surface charge. The lipid/PDA film system, in conjunction with the calixarene-derived ligands, facilitates characterization of protein surface charges and identification of anomalous protein electrostatic properties.
authors.affiliation: Department of Chemistry and Ilse Katz Institute for Nanotechnology, Ben Gurion University, Beer Sheva, Israel 84105.
authors.forename: Sarit
authors.initials: S
authors.lastname: Friedman
authors.forename: Sofiya
authors.initials: S
authors.lastname: Kolusheva
authors.forename: Roman
authors.initials: R
authors.lastname: Volinsky
authors.forename: Leila
authors.initials: L
authors.lastname: Zeiri
authors.forename: Thomas
authors.initials: T
authors.lastname: Schrader
authors.forename: Raz
authors.initials: R
authors.lastname: Jelinek
mesh_terms: D000818:Animals; D047250:Calixarenes / Q000737:chemistry; D002417:Cattle; D003124:Colorimetry / Q000379:methods*; D008024:Ligands; D010743:Phospholipids / Q000737:chemistry*; D000078789:Polyacetylene Polymer; D011108:Polymers / Q000737:chemistry*; D053279:Polyynes / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D012995:Solubility; D055672:Static Electricity; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D008024:Ligands; D010743:Phospholipids; D000078789:Polyacetylene Polymer; D011108:Polymers; D011506:Proteins; D014867:Water; D047250:Calixarenes; D053279:Polyynes; C082361:polydiacetylene