title: Formation of enzyme polymer engineered structure for laccase and cross-linked laccase aggregates stabilization.
abstract: Laccase and laccase-based cross-linked enzyme aggregates (CLEAs) were stabilized through the formation of a surrounding polymeric network made of chitosan and 3-aminopropyltriethoxysilane. The thermoresistance of the resulting enzyme polymer engineered structures of laccase (EPES-lac) and CLEAs (EPES-CLEA) were more than 30 times higher than that of free laccase and CLEAs at pH 3 and 40 °C. The EPES showed higher residual activity than the unmodified biocatalysts against chaotropic salts (up to 10 times), EDTA (up to 5 times), methanol (up to 15 times) and acetone (up to 20 times). The Michaelis-Menten kinetic parameters revealed that the affinity for 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) has doubled for the EPES-lac and EPES CLEA compared to their unmodified forms. The EPES-lac structures acted optimally at pH 4 and their activity was nearly temperature-independent, while the laccase activity of EPES-CLEA was optimal at pH 4 and 60 °C. Globally, the EPES have shown significantly improved properties which make them attractive candidate for the development of laccase-based applications.
authors.affiliation: Environmental Engineering Laboratory, Department of Civil Engineering, University of Sherbrooke, 2500 Boulevard de l'Université, Sherbrooke, Quebec, Canada J1K 2R1.
authors.forename: Thanina
authors.initials: T
authors.lastname: Hassani
authors.forename: Sidy
authors.initials: S
authors.lastname: Ba
authors.forename: Hubert
authors.initials: H
authors.lastname: Cabana
mesh_terms: D048271:Chitosan / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D042845:Laccase / Q000737:chemistry*; D011437:Propylamines; D015202:Protein Engineering / Q000379:methods; D012821:Silanes / Q000737:chemistry*; D013696:Temperature
chemical_list: D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D011437:Propylamines; D012821:Silanes; D048271:Chitosan; D042845:Laccase; C477625:amino-propyl-triethoxysilane