title: Streptavidin as a macroinitiator for polymerization: in situ protein-polymer conjugate formation.
abstract: This communication reports the first example of polymerization initiated from specific domains on proteins. Streptavidin was coupled with a biotinylated initiator for atom transfer radical polymerization (ATRP) and exposed to an aqueous solution of CuBr/2,2'-bipyridine and monomer. N-Isopropylacrylamide (NIPAAm) and poly(ethylene glycol) methyl ether methacrylate (PEGMA) were readily initiated by the modified streptavidin and polymerized from the protein at room temperature. Formation of streptavidin-polymer conjugates was confirmed by size exclusion chromatography (SEC) and gel electrophoresis. Polymer identity and biotinylation was verified using 1H NMR spectroscopy, gel permeation chromatography (GPC), and surface plasmon resonance (SPR) after dissociation of the biotin-streptavidin complex. This general approach is likely to be extended to other proteins and monomers and promises to enable easy synthesis and purification of a variety of polymer-protein conjugates.
authors.affiliation: Department of Chemistry and Biochemistry & California Nanosystems Institute, University of California-Los Angeles, 607 Charles E. Young Drive East, Los Angeles, CA 90095-1569, USA.
authors.forename: Debora
authors.initials: D
authors.lastname: Bontempo
authors.forename: Heather D
authors.initials: HD
authors.lastname: Maynard
mesh_terms: D000178:Acrylamides / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D008958:Models, Molecular; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry; D019809:Streptavidin / Q000737:chemistry*
chemical_list: D000178:Acrylamides; D011108:Polymers; D011109:Polymethacrylic Acids; C030613:polymethacrylic acid; D011092:Polyethylene Glycols; D019809:Streptavidin; C067295:N-isopropylacrylamide