title: Lytic polysaccharide monooxygenases disrupt the cellulose fibers structure.
abstract: Lytic polysaccharide monooxygenases (LPMOs) are a class of powerful oxidative enzymes that breakdown recalcitrant polysaccharides such as cellulose. Here we investigate the action of LPMOs on cellulose fibers. After enzymatic treatment and dispersion, LPMO-treated fibers show intense fibrillation. Cellulose structure modifications visualized at different scales indicate that LPMO creates nicking points that trigger the disintegration of the cellulose fibrillar structure with rupture of chains and release of elementary nanofibrils. Investigation of LPMO action using solid-state NMR provides direct evidence of modification of accessible and inaccessible surfaces surrounding the crystalline core of the fibrils. The chains breakage likely induces modifications of the cellulose network and weakens fibers cohesion promoting their disruption. Besides the formation of new initiation sites for conventional cellulases, this work provides the first evidence of the direct oxidative action of LPMOs with the mechanical weakening of the cellulose ultrastructure. LPMOs can be viewed as promising biocatalysts for enzymatic modification or degradation of cellulose fibers.
authors.affiliation: BIA, INRA, 44300, Nantes, France.
authors.forename: Ana
authors.initials: A
authors.lastname: Villares
authors.affiliation: BIA, INRA, 44300, Nantes, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Moreau
authors.affiliation: Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille Univ, UMR1163, 13009, Marseille, France.
authors.forename: Chloé
authors.initials: C
authors.lastname: Bennati-Granier
authors.affiliation: Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille Univ, UMR1163, 13009, Marseille, France.
authors.forename: Sona
authors.initials: S
authors.lastname: Garajova
authors.affiliation: BIA, INRA, 44300, Nantes, France.
authors.forename: Loïc
authors.initials: L
authors.lastname: Foucat
authors.affiliation: BIA, INRA, 44300, Nantes, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Falourd
authors.affiliation: Chemical Wood Technology, University of Hamburg, Leuschnerstraße 91b, 21031 Hamburg, Germany.
authors.forename: Bodo
authors.initials: B
authors.lastname: Saake
authors.affiliation: Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille Univ, UMR1163, 13009, Marseille, France.
authors.forename: Jean-Guy
authors.initials: JG
authors.lastname: Berrin
authors.affiliation: BIA, INRA, 44300, Nantes, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Cathala
mesh_terms: D002482:Cellulose / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D011134:Polysaccharides / Q000378:metabolism*; D014934:Wood / Q000737:chemistry / Q000201:enzymology
chemical_list: D011134:Polysaccharides; D002482:Cellulose; D006899:Mixed Function Oxygenases