title: Assessment of in vitro binding of isolated pectic domains to cellulose by adsorption isotherms, electron microscopy, and X-ray diffraction methods.
abstract: Isolated pectic domains representative of the pectic backbone and the neutral sugar side chains were tested for their ability to interact with cellulose in comparison to the well-known binding of xyloglucan. Pectic side chains displayed a significant in vitro binding capacity to cellulose, whereas pectic backbone domains exhibited only slight adsorption to cellulose microfibrils. To support the binding results, electron microscopy and X-ray diffraction were applied. Celluloses from bacteria and sugar beet cell walls were used as substrates for the precipitation of isolated pectic domains or xyloglucan by acetone vapor diffusion. Pectic side chains grew attached to the cellulose surfaces, whereas pectic backbone domains were observed separately from cellulose microfibrils. Xyloglucan seeded with cellulose provoked a decrease of microfibrils entanglement, but no clear cross-links between neighboring microfibrils were observed. These results led to the elucidation of the pectic domains responsible for binding with cellulose microfibrils.
authors.affiliation: INRA, Unité de Recherche Biopolymères, Interactions, Assemblages, BP 71627, 44316 Nantes Cedex 03, France.
authors.forename: Agata
authors.initials: A
authors.lastname: Zykwinska
authors.forename: Cédric
authors.initials: C
authors.lastname: Gaillard
authors.forename: Alain
authors.initials: A
authors.lastname: Buléon
authors.forename: Bruno
authors.initials: B
authors.lastname: Pontoire
authors.forename: Catherine
authors.initials: C
authors.lastname: Garnier
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Thibault
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Ralet
mesh_terms: D000327:Adsorption; D002473:Cell Wall / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry*; D004058:Diffusion; D005936:Glucans / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D006860:Hydrogen Bonding; D008854:Microscopy, Electron / Q000379:methods; D046529:Microscopy, Electron, Transmission; D010368:Pectins / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D012542:Scattering, Radiation; D014961:X-Ray Diffraction; D014965:X-Rays
chemical_list: D005936:Glucans; D011134:Polysaccharides; D006859:Hydrogen; D010368:Pectins; D002482:Cellulose