Characterization of nematode glycoproteins: the major O-glycans of Toxocara excretory-secretory antigens are O-methylated trisaccharides.
Toxocara excretory-secretory antigens (TES) were isolated from the culture media of T.canis and T.cati larvae and their O-glycan content was investigated using fast atom bombardment-mass spectrometry (FAB-MS), gas chromatography and electron impact mass spectrometry. The major oligosaccharides released by reductive elimination of T.canis TES glycoproteins were shown to be two, approximately equi-abundant, trisaccharides: 2-O-Me-Fucp(alpha 1----2)-4-O-Me-Galp(beta 1----3)GalNAcitol and 2-O-Me-Fucp(alpha 1----2)-Galp(beta 1----3)GalNAcitol. In contrast T.cati TES O-glycans are predominantly one component, shown by FAB-MS to be a di-O-methylated trisaccharide, which is probably identical to the di-O-methylated trisaccharide from T.canis. The O-methylated trisaccharides are strong candidates for the carbohydrate epitopes recognized by a panel of monoclonal antibodies which exhibit multiple reactivity against TES antigens. This study constitutes the first rigorous characterization of glycans from a parasitic nematode.
Khoo
K H
KH
Department of Biochemistry, Imperial College of Science, London, UK.
Maizels
R M
RM
Page
A P
AP
Taylor
G W
GW
Rendell
N B
NB
Dell
A
A
D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D006023:Glycoproteins / Q000737:chemistry* / Q000302:isolation & purification; D007814:Larva; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014119:Toxocara / Q000737:chemistry*
D006023:Glycoproteins; D009844:Oligosaccharides