title: Enzymatic Activities of Polycatalytic Complexes with Nonprocessive Cellulases Immobilized on the Surface of Magnetic Nanoparticles.
abstract: Polycatalytic enzyme complexes made by immobilization of industrial enzymes on polymer- or nanoparticle-based scaffolds are technologically attractive due to their recyclability and their improved substrate binding and catalytic activities. Herein, we report the synthesis of polycatalytic complexes by the immobilization of nonprocessive cellulases on the surface of colloidal polymers with a magnetic nanoparticle core and the study of their binding and catalytic activities. These polycatalytic cellulase complexes have increased binding affinity for the substrate. But due to their larger size, these complexes were unable to access to the internal surfaces of cellulose and have significantly lower binding capacity when compared to those of the corresponding free enzymes. Analysis of released soluble sugars indicated that the formation of complexes may promote the prospect of having consistent, multiple attacks on cellulose substrate. Once bound to the substrate, polycatalytic complexes tend to remain on the surface with very limited mobility due to their strong, multivalent binding to cellulose. Hence, the overall performance of polycatalytic complexes is limited by its substrate accessibility as well as mobility on the substrate surface.
authors: Ranjan K
authors: RK
authors: Kamat
authors: State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan University , Shanghai 200433, China.
authors: Yuting
authors: Y
authors: Zhang
authors: Murali
authors: M
authors: Anuganti
authors: State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan University , Shanghai 200433, China.
authors: Wanfu
authors: W
authors: Ma
authors: Iman
authors: I
authors: Noshadi
authors: Hailin
authors: H
authors: Fu
authors: Stephen
authors: S
authors: Ekatan
authors: Richard
authors: R
authors: Parnas
authors: State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan University , Shanghai 200433, China.
authors: Changchun
authors: C
authors: Wang
authors: Challa V
authors: CV
authors: Kumar
authors: Yao
authors: Y
authors: Lin
mesh_terms: D002475:Cellobiose / Q000737:chemistry; D044602:Cellulases / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry*; D003102:Colloids; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005656:Fungal Proteins / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry; D007700:Kinetics; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011109:Polymethacrylic Acids / Q000737:chemistry*; D011485:Protein Binding; D013379:Substrate Specificity
chemical_list: D003102:Colloids; D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D058185:Magnetite Nanoparticles; D011109:Polymethacrylic Acids; D002475:Cellobiose; C030613:polymethacrylic acid; D002482:Cellulose; D044602:Cellulases; D005947:Glucose