title: The opportunistic fungal pathogen Scedosporium prolificans: carbohydrate epitopes of its glycoproteins.
abstract: Isolated from the mycelium of Scedosporium prolificans were complex glycoproteins (RMP-Sp), with three structurally related components (HPSEC). RMP-Sp contained 35% protein and 62% carbohydrate with Rha, Ara, Man, Gal, Glc, and GlcNH(2) in a 18:1:24:8:6:5 molar ratio. Methylation analysis showed mainly nonreducing end- of Galp (13%), nonreducing end- (9%), 2-O- (13%), and 3-O-subst. Rhap (7%), nonreducing end- (11%), 2-O- (10%), 3-O- (14%), and 2,6-di-O-subst. Manp units (13%). Mild reductive beta-elimination of RMP-Sp gave alpha-l-Rhap-(1-->2)-alpha-l-Rhap-(1-->3)-alpha-l-Rhap-(1-->3)-alpha-d-Manp-(1-->2)-d-Man-ol, with Man-ol substituted at O-6 with beta-d-Galp units, a related pentasaccharide lacking beta-d-Galp units, and beta-d-Galp-(1-->6)-[alpha-d-Manp-(1-->2)]-d-Man-ol in a 16:3:1w/w ratio. Traces of Man-ol and Rha-ol were detected. ESI-MS showed HexHex-ol and Hex(3-6)Hex-ol components. Three rhamnosyl units were peeled off successively from the penta- and hexasaccharide by ESI-MS-MS. The carbohydrate epitopes of RMP-Sp differ from those of the glycoprotein of Pseudallescheria boydii, a related opportunistic pathogen.
authors.affiliation: Instituto de Microbiologia, C.C.S., Universidade Federal do Rio de Janeiro, 21944-590 Rio de Janeiro, RJ, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Barreto-Bergter
authors.forename: G L
authors.initials: GL
authors.lastname: Sassaki
authors.forename: R
authors.initials: R
authors.lastname: Wagner
authors.forename: L M
authors.initials: LM
authors.lastname: Souza
authors.forename: M V A R
authors.initials: MV
authors.lastname: Souza
authors.forename: M R
authors.initials: MR
authors.lastname: Pinto
authors.forename: M I D
authors.initials: MI
authors.lastname: da Silva
authors.forename: P A J
authors.initials: PA
authors.lastname: Gorin
mesh_terms: D002240:Carbohydrate Sequence; D000939:Epitopes / Q000737:chemistry* / Q000276:immunology*; D006023:Glycoproteins / Q000737:chemistry* / Q000276:immunology*; D009682:Magnetic Resonance Spectroscopy; D009844:Oligosaccharides / Q000737:chemistry; D021681:Scedosporium / Q000737:chemistry / Q000276:immunology* / Q000472:pathogenicity*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000939:Epitopes; D006023:Glycoproteins; D009844:Oligosaccharides