title: Graphene oxide derivatives with variable alkyl chain length and terminal functional groups as supports for stabilization of cytochrome c.
abstract: In this study we report the ability of reduced and non-reduced graphene oxide-based nanomaterials (GONs), modified with variable alkyl chain length and terminal functional groups, to act as effective scaffolds for the immobilization of cytochrome c (cyt c) using different immobilization procedures. The GONs/cyt c conjugates are characterized by a combination of techniques, namely atomic force microscopy, X-ray photoelectron and FT-IR spectroscopies as well as thermo-gravimetric and differential thermal analysis. The effect of the structure of functional groups and the surface chemistry of GONs on the immobilization efficiency, the peroxidase activity and the stability of the cyt c was investigated and correlated with conformational changes on the protein molecule upon immobilization. The enhanced thermal stability (up to 2-fold) and increased tolerance (up to 25-fold) against denaturing agents observed for immobilized cyt c, indicates that these functionalized GONs are suitable as nanoscaffolds for the development of robust nanobiocatalysts.
authors.affiliation: Biotechnology Laboratory, Department of Biological Applications and Technologies, University of Ioannina, 45110 Ioannina, Greece.
authors.forename: Michaela
authors.initials: M
authors.lastname: Patila
authors.affiliation: Department of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, 17487 Greifswald, Germany.
authors.forename: Ioannis V
authors.initials: IV
authors.lastname: Pavlidis
authors.affiliation: Department of Material Science and Engineering, University of Ioannina, 45110 Ioannina, Greece.
authors.forename: Antonios
authors.initials: A
authors.lastname: Kouloumpis
authors.affiliation: Department of Material Science and Engineering, University of Ioannina, 45110 Ioannina, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Dimos
authors.affiliation: Department of Material Science and Engineering, University of Ioannina, 45110 Ioannina, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Spyrou
authors.affiliation: Biotechnology Laboratory, Department of Biological Applications and Technologies, University of Ioannina, 45110 Ioannina, Greece.
authors.forename: Petros
authors.initials: P
authors.lastname: Katapodis
authors.affiliation: Department of Material Science and Engineering, University of Ioannina, 45110 Ioannina, Greece.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Gournis
authors.affiliation: Biotechnology Laboratory, Department of Biological Applications and Technologies, University of Ioannina, 45110 Ioannina, Greece. Electronic address: hstamati@uoi.gr.
authors.forename: Haralambos
authors.initials: H
authors.lastname: Stamatis
mesh_terms: D000818:Animals; D002384:Catalysis; D045304:Cytochromes c / Q000737:chemistry* / Q000378:metabolism; D004789:Enzyme Activation; D004795:Enzyme Stability; D004800:Enzymes, Immobilized; D006108:Graphite / Q000737:chemistry*; D006736:Horses; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry
chemical_list: D004800:Enzymes, Immobilized; D010087:Oxides; D006108:Graphite; D045304:Cytochromes c
keywords: Cytochrome c; Graphene-oxide; Immobilization; Nanobiocatalysis; Nanomaterials