title: Structural characterization of N-linked oligosaccharides from cellobiohydrolase I secreted by the filamentous fungus Trichoderma reesei RUTC 30.
abstract: We have characterized the primary structures of the predominant N-linked oligosaccharides on cellobiohydrolase I from the filamentous fungus Trichoderma reesei RUTC30. Different enzymatic and chromatographic techniques were used to analyze six oligosaccharides. The combined data showed that the fungal carbohydrates have a core structure that is identical to the mammalian N-linked core. In the bulk of the N-glycans, the alpha-1,3 arm is extended with two mannoses and a glucose, suggesting incomplete processing of the oligosaccharides in the endoplasmic reticulum. The alpha-1,6 arm shows a remarkable heterogeneity: in addition to alpha-1,2-Man and alpha-1,6-Man, the presence of a terminal mannose alpha-1,6-phosphodiester was observed. This latter substituent has not been characterized before on mannosidase-processed N-glycan and its function and synthesis pathway are entirely unknown. The predominant N-glycans on cellobiohydrolase I can be represented as follows: GlcMan8GlcNAc2, GlcMan7GlcNAc2, Man7GlcNAc2, ManPGlcMan7GlcNAc2, GlcMan5GlcNAc2 and Man5GlcNAc2.
authors.affiliation: Laboratory of Molecular Biology, Flanders Interuniversity Institute for Biotechnology and University of Ghent, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Maras
authors.forename: A
authors.initials: A
authors.lastname: De Bruyn
authors.forename: J
authors.initials: J
authors.lastname: Schraml
authors.forename: P
authors.initials: P
authors.lastname: Herdewijn
authors.forename: M
authors.initials: M
authors.lastname: Claeyssens
authors.forename: W
authors.initials: W
authors.lastname: Fiers
authors.forename: R
authors.initials: R
authors.lastname: Contreras
mesh_terms: D002240:Carbohydrate Sequence; D002480:Cellulase / Q000737:chemistry*; D043366:Cellulose 1,4-beta-Cellobiosidase; D005656:Fungal Proteins / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000032:analysis*; D014242:Trichoderma / Q000737:chemistry* / Q000201:enzymology
chemical_list: D005656:Fungal Proteins; D009844:Oligosaccharides; D002480:Cellulase; D043366:Cellulose 1,4-beta-Cellobiosidase