title: Recyclable nanobiocatalyst for enantioselective sulfoxidation: facile fabrication and high performance of chloroperoxidase-coated magnetic nanoparticles with iron oxide core and polymer shell.
abstract: Magnetic nanoparticles (MNPs) with a core diameter of 30 nm comprising several iron oxide crystals, a poly(glycidyl methacrylate) (PGMA) shell with a thickness of 30 nm, and a surface coated with chloroperoxidase (CPO) were facilely fabricated as a nanobiocatalyst for asymmetric sulfoxidation. The covalently bound CPO did not change the original conformation of the active site and showed the same catalytic activity and enantioselectivity as free CPO for the sulfoxidation of thioanisole to produce (R)-methyl phenyl sulfoxide in >99% ee. The thick PGMA shell significantly increased the stability of the nanobiocatalyst: no loss of the sulfoxidation activity was observed after 11 times of recycling and reuse of the catalyst. Thus, the nanobiocatalyst fabricated here showed the best performance among nanosized biocatalyst particles regarding both the retaining of free enzyme activity and the recycling of catalyst. This is also the first example of a nanobiocatalyst for asymmetric oxidation, and the concept could be generally applicable for fabricating active and recyclable nanobiocatalysts.
authors.affiliation: Singapore-MIT Alliance, Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576.
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
authors.forename: Daniel I C
authors.initials: DI
authors.lastname: Wang
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
mesh_terms: D055162:Biocatalysis; D002711:Chloride Peroxidase / Q000737:chemistry / Q000378:metabolism*; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D005290:Ferric Compounds / Q000737:chemistry*; D008280:Magnetics; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D011109:Polymethacrylic Acids / Q000737:chemistry*; D013237:Stereoisomerism; D013440:Sulfides / Q000378:metabolism
chemical_list: D004800:Enzymes, Immobilized; D005290:Ferric Compounds; D011109:Polymethacrylic Acids; D013440:Sulfides; C000499:ferric oxide; C042535:polyglycidyl methacrylate; C093850:methylphenylsulfide; D002711:Chloride Peroxidase