Covalent attachment of cyclodextrin glucanotransferase from genetically modified Escherichia coli on surface functionalized silica coated carriers and magnetic particles

Correspondence: Viara Ivanova University of Food Technologies – Plovdiv, Department of Microbiology, 26 Maritsa Blvd., 4002 Plovdiv, Bulgaria. Tel.: +359 32 603622 e-mail: [email protected] ABSTRACT Recombinant cyclodextrin glucanotransferase JCGT8-5 (CGTase, EC 2.4.1.19) was effectively immobilized by formation of chemical bounds on polyethylenimine (PEI)-activated silica particles, on silanized Spherosils 5, XOA200, XOC 005, Arylamine CPG and magnetite Fe3O4 (Fe(II)O.Fe(III)2O3) micro-particles and by adsorption on magnetite/activated carbon support. The immobilization capacities of the carriers were determined. Binding yields reached from 50% to 93%. The amount of bound enzyme was considerably higher when this protein was immobilized on polyethylenimine (PEI)-activated silica particles and silanized Spherosil 5, XOA and XOC micro-particles and reached 1.33-1.77 mg/g support. Arylamine CPG and the activated carbon/magnetite support also possessed high binding capacities – 0.73-0.78 mg enzyme/g carrier. Analysis of formed CDs revealed changes in the β-cyclodextrin: γ-cyclodextrin ratio due to immobilization.