title: Characterization of deoxyribonuclease I immobilized on magnetic hydrophilic polymer particles.
abstract: Magnetic bead cellulose particles and magnetic poly(HEMA-co-EDMA) microspheres with immobilized DNase I were used for degradation of chromosomal and plasmid DNAs. Magnetic bead particles were prepared from viscose and magnetite powder. Magnetic poly(HEMA-co-EDMA) microspheres were prepared by dispersion copolymerization of 2-hydroxyethyl methacrylate and ethylene dimethacrylate in the presence of magnetite. Divalent cations (Mg(2+), Ca(2+), Mn(2+) and Co(2+)) were used for the activation of DNase I. A comparison of free and immobilized enzyme (magnetic bead particles) activities was carried out in dependence on pH and activating cation. The maximum of the activity of immobilized DNase I was shifted to lower pH compared with free DNase I. DNase I immobilized on magnetic bead cellulose was used 20 times in the degradation of chromosomal DNA. Its residual activity was influenced by the nature of activating divalent cation. The immobilized enzyme with decreased activity was reactivated by Co(2+) ions.
authors.affiliation: Department of Microbiology, Faculty of Science, Masaryk University Brno, Tvrdého 14, CZ-602 00 Brno, Czech Republic. rittich@sci.muni.cz
authors.forename: Bohuslav
authors.initials: B
authors.lastname: Rittich
authors.forename: Alena
authors.initials: A
authors.lastname: Spanová
authors.forename: Yuriy
authors.initials: Y
authors.lastname: Ohlashennyy
authors.forename: Jirí
authors.initials: J
authors.lastname: Lenfeld
authors.forename: Ivo
authors.initials: I
authors.lastname: Rudolf
authors.forename: Daniel
authors.initials: D
authors.lastname: Horák
authors.forename: Milan J
authors.initials: MJ
authors.lastname: Benes
mesh_terms: D002413:Cations, Divalent; D003850:Deoxyribonuclease I / Q000378:metabolism*; D004587:Electrophoresis, Agar Gel; D004789:Enzyme Activation; D004800:Enzymes, Immobilized / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008280:Magnetics; D008863:Microspheres; D010957:Plasmids; D011108:Polymers / Q000737:chemistry*
chemical_list: D002413:Cations, Divalent; D004800:Enzymes, Immobilized; D011108:Polymers; D003850:Deoxyribonuclease I