Planarial species are of especial interest to biologists due to the phenomenon of pluripotency and, in comparison to other developmental processes, it can be hypothesised that glycan-lectin interactions may play a role. In order to examine the N-glycans of one of these organisms, Dugesia japonica, peptide:N-glycosidase A was employed and the released glycans were subject to pyridylamination, HPLC and mass spectrometric analysis. A range of oligomannosidic glycans was observed with a trimethylated Man(5) GlcNAc(2) structure being the dominant species. Three glycans were also observed to contain deoxyhexose; in particular, a glycan with the composition Hex(4) HexNAc(2) Fuc(1) Me(2) was revealed by exoglycosidase digestion, in combination with MS/MS, to contain a galactosylated core α1,6-fucose residue, whereas this core modification was found to be capped with a methylhexose residue in the case of a Hex(5) HexNAc(2) Fuc(1) Me(3) structure. This is the first report of these types of structures in a platyhelminth and indicates that the "GalFuc" modification of N-glycans is not just restricted to molluscs and nematodes.
Animals Carbohydrate Conformation Chromatography, High Pressure Liquid Fucose/chemistry* Fucose/metabolism Galactose/chemistry* Galactose/metabolism Methylation Oligosaccharides/chemistry Oligosaccharides/metabolism Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase/chemistry Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase/metabolism Planarians/chemistry* Planarians/metabolism Polysaccharides/chemistry* Polysaccharides/metabolism Tandem Mass Spectrometry