title: Efficient and stable enzyme immobilization in a block copolypeptide vesicle-templated biomimetic silica support.
abstract: We report the immobilization of a model enzyme, papain, within silica matrices by combining vesiclization of poly-l-lysine-b-polyglycine block copolypeptides with following silica mineralization. Our novel strategy utilizes block polypeptide vesicles to induce the condensation of orthosilicic acid while trapping an enzyme within and between vesicles. The polypeptide mediated silica-immobilized enzyme exhibits enhanced pH and thermal stability and reusability, comparing with the free and vesicle encapsulated enzyme. The enhanced enzymatic activity in the immobilized enzyme is due to the confinement of the enzyme in the polypeptide mediated silica matrices. Kinetic analysis shows that the enzyme functionality is determined by the structure and property of silica/polypeptide matrices. The proposed novel strategy provides an alternative route for the synthesis of a broad range of functional bionanocomposites entrapped within silica nanostructures.
authors.affiliation: Department of Chemical Engineering, National Taiwan University, No. 1, Sec 4, Roosevelt Rd., Taipei 10617, Taiwan.
authors.forename: Jun-Kun
authors.initials: JK
authors.lastname: Lai
authors.forename: Tzu-Han
authors.initials: TH
authors.lastname: Chuang
authors.forename: Jeng-Shiung
authors.initials: JS
authors.lastname: Jan
authors.forename: Steven Sheng-Shih
authors.initials: SS
authors.lastname: Wang
mesh_terms: D040761:Biomimetic Materials / Q000737:chemistry*; D032701:Biomimetics / Q000379:methods; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D010206:Papain / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D010455:Peptides / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature
chemical_list: D004800:Enzymes, Immobilized; D010455:Peptides; D012822:Silicon Dioxide; D010206:Papain