Enzymatic nanoreactors for environmentally benign biotransformations. 1. Formation and catalytic activity of supramolecular complexes of laccase and linear-dendritic block copolymers.
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.
Gitsov
Ivan
I
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
Hamzik
James
J
Ryan
Joseph
J
Simonyan
Arsen
A
Nakas
James P
JP
Omori
Shigetoshi
S
Krastanov
Albert
A
Cohen
Tomer
T
Tanenbaum
Stuart W
SW
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
D050091:Dendrimers; D006023:Glycoproteins; D010636:Phenols; D011084:Polycyclic Aromatic Hydrocarbons; D011092:Polyethylene Glycols; D042845:Laccase