title: Enzymatic nanoreactors for environmentally benign biotransformations. 1. Formation and catalytic activity of supramolecular complexes of laccase and linear-dendritic block copolymers.
abstract: We describe the construction of enzymatic nanoreactors through noncovalent envelopment of a glycoprotein by amphiphilic linear-dendritic AB or ABA copolymers. The synthetic procedure is based on the regioselective adsorption of dendritic poly(benzyl ether)-block-linear poly(ethylene glycol)-block-dendritic poly(benzyl ether) or linear poly(ethylene oxide)-block-dendritic poly(benzyl ether) copolymers onto the oxidative enzyme laccase from Trametes versicolor in aqueous medium. The complexes formed have improved catalytic activity compared with the native enzyme (77-85 nkat/mL vs 60 nkat/mL, respectively) and are more stable at elevated temperatures up to 70 degrees C. Experiments with deglycosylated laccase confirm that the glycoside fragments in the native enzyme serve as the anchor sites for the linear-dendritic copolymers. The enzymatic nanoreactors are able to effectively oxidize series of substrates: phenolic compounds (syringaldazine) and hydrophobic polyaromatic hydrocarbons (anthracene and benzo[a]pyrene) under "green" chemistry conditions.
authors.affiliation: The Michael M. Szwarc Polymer Research Institute, State University of New York College of Environmental Science and Forestry, Syracuse, New York 13210, USA. igivanov@syr.edu
authors.forename: Ivan
authors.initials: I
authors.lastname: Gitsov
authors.forename: James
authors.initials: J
authors.lastname: Hamzik
authors.forename: Joseph
authors.initials: J
authors.lastname: Ryan
authors.forename: Arsen
authors.initials: A
authors.lastname: Simonyan
authors.forename: James P
authors.initials: JP
authors.lastname: Nakas
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Omori
authors.forename: Albert
authors.initials: A
authors.lastname: Krastanov
authors.forename: Tomer
authors.initials: T
authors.lastname: Cohen
authors.forename: Stuart W
authors.initials: SW
authors.lastname: Tanenbaum
mesh_terms: D001673:Biodegradation, Environmental; D019149:Bioreactors; D002384:Catalysis; D050091:Dendrimers / Q000138:chemical synthesis / Q000737:chemistry*; D006023:Glycoproteins / Q000737:chemistry; D042845:Laccase / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010084:Oxidation-Reduction; D010636:Phenols / Q000378:metabolism; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism; D011092:Polyethylene Glycols / Q000737:chemistry; D020072:Polyporales / Q000201:enzymology
chemical_list: D050091:Dendrimers; D006023:Glycoproteins; D010636:Phenols; D011084:Polycyclic Aromatic Hydrocarbons; D011092:Polyethylene Glycols; D042845:Laccase