title: Cello-oligosaccharide oxidation reveals differences between two lytic polysaccharide monooxygenases (family GH61) from Podospora anserina.
abstract: The genome of the coprophilic ascomycete Podospora anserina encodes 33 different genes encoding copper-dependent lytic polysaccharide monooxygenases (LPMOs) from glycoside hydrolase family 61 (GH61). In this study, two of these enzymes (P. anserina GH61A [PaGH61A] and PaGH61B), which both harbored a family 1 carbohydrate binding module, were successfully produced in Pichia pastoris. Synergistic cooperation between PaGH61A or PaGH61B with the cellobiose dehydrogenase (CDH) of Pycnoporus cinnabarinus on cellulose resulted in the formation of oxidized and nonoxidized cello-oligosaccharides. A striking difference between PaGH61A and PaGH61B was observed through the identification of the products, among which were doubly and triply oxidized cellodextrins, which were released only by the combination of PaGH61B with CDH. The mass spectrometry fragmentation patterns of these oxidized products could be consistent with oxidation at the C-6 position with a geminal diol group. The different properties of PaGH61A and PaGH61B and their effect on the interaction with CDH are discussed in regard to the proposed in vivo function of the CDH/GH61 enzyme system in oxidative cellulose hydrolysis.
authors.affiliation: INRA, UMR1163 BCF, Marseille, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Bey
authors.forename: Simeng
authors.initials: S
authors.lastname: Zhou
authors.forename: Laetitia
authors.initials: L
authors.lastname: Poidevin
authors.forename: Bernard
authors.initials: B
authors.lastname: Henrissat
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Coutinho
authors.forename: Jean-Guy
authors.initials: JG
authors.lastname: Berrin
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Sigoillot
mesh_terms: D002237:Carbohydrate Dehydrogenases / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism; D003001:Cloning, Molecular; D015870:Gene Expression; D013058:Mass Spectrometry; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D009844:Oligosaccharides / Q000378:metabolism*; D010084:Oxidation-Reduction; D010843:Pichia / Q000235:genetics; D048468:Podospora / Q000201:enzymology*; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D009844:Oligosaccharides; D011994:Recombinant Proteins; D002482:Cellulose; D006899:Mixed Function Oxygenases; D002237:Carbohydrate Dehydrogenases; C019859:cellobiose-quinone oxidoreductase