title: Tunable Semicrystalline Thin Film Cellulose Substrate for High-Resolution, In-Situ AFM Characterization of Enzymatic Cellulose Degradation.
abstract: In the field of enzymatic cellulose degradation, fundamental interactions between different enzymes and polymorphic cellulose materials are of essential importance but still not understood in full detail. One technology with the potential of direct visualization of such bioprocesses is atomic force microscopy (AFM) due to its capability of real-time in situ investigations with spatial resolutions down to the molecular scale. To exploit the full capabilities of this technology and unravel fundamental enzyme-cellulose bioprocesses, appropriate cellulose substrates are decisive. In this study, we introduce a semicrystalline-thin-film-cellulose (SCFTC) substrate which fulfills the strong demands on such ideal cellulose substrates by means of (1) tunable polymorphism via variable contents of homogeneously sized cellulose nanocrystals embedded in an amorphous cellulose matrix; (2) nanoflat surface topology for high-resolution and high-speed AFM; and (3) fast, simple, and reproducible fabrication. The study starts with a detailed description of SCTFC preparation protocols including an in-depth material characterization. In the second part, we demonstrate the suitability of SCTFC substrates for enzymatic degradation studies by combined, individual, and sequential exposure to TrCel6A/TrCel7A cellulases (Trichoderma reesei) to visualize synergistic effects down to the nanoscale.
authors.affiliation: Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Ganner
authors.affiliation: Graz Centre for Electron Microscopy , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Roŝker
authors.affiliation: Institute of Biotechnology and Biochemical Engineering, Graz University of Technology , Petersgasse 12, A-8010 Graz, Austria.
authors.forename: Manuel
authors.initials: M
authors.lastname: Eibinger
authors.affiliation: Graz Centre for Electron Microscopy , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Johanna
authors.initials: J
authors.lastname: Kraxner
authors.affiliation: Graz Centre for Electron Microscopy , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Sattelkow
authors.affiliation: Graz Centre for Electron Microscopy , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Johannes
authors.initials: J
authors.lastname: Rattenberger
authors.affiliation: Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Harald
authors.initials: H
authors.lastname: Fitzek
authors.affiliation: Graz Centre for Electron Microscopy , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Boril
authors.initials: B
authors.lastname: Chernev
authors.affiliation: Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology , Steyrergasse 17, A-8010 Graz, Austria.|Graz Centre for Electron Microscopy , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Werner
authors.initials: W
authors.lastname: Grogger
authors.affiliation: Institute of Biotechnology and Biochemical Engineering, Graz University of Technology , Petersgasse 12, A-8010 Graz, Austria.|Austrian Centre of Industrial Biotechnology , Petersgasse 14, A-8010 Graz, Austria.
authors.forename: Bernd
authors.initials: B
authors.lastname: Nidetzky
authors.affiliation: Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology , Steyrergasse 17, A-8010 Graz, Austria.|Graz Centre for Electron Microscopy , Steyrergasse 17, A-8010 Graz, Austria.
authors.forename: Harald
authors.initials: H
authors.lastname: Plank
mesh_terms: D044602:Cellulases / Q000737:chemistry* / Q000378:metabolism; D002482:Cellulose / Q000737:chemistry* / Q000648:ultrastructure; D006868:Hydrolysis; D007700:Kinetics; D018625:Microscopy, Atomic Force; D013379:Substrate Specificity; D014242:Trichoderma / Q000201:enzymology
chemical_list: D002482:Cellulose; D044602:Cellulases
keywords: atomic force microscope (AFM); cellulase; cellulose model substrate; enzymatic cellulose degradation; nanocrystalline cellulose (NCC)