Novel (rhamnosyl and ribosyl) and uncommon (xylosyl) monosaccharide residues are present in asparagine-linked oligosaccharides of the trypanosomatid Blastocrithidia culicis.
Blastocrithidia culicis is a trypanosomatid protozoon that transfers Man6GlcNAc2 in protein N-glycosylation. Compounds containing mannosyl, xylosyl, and rhamnosyl residues were found among the endo-beta-N-acetylglucosaminidase H-sensitive oligosaccharides of whole cell glycoproteins of this parasite. The compositions of some of them were as follows: Man5GlcNAc2, Man6GlcNAc2, Rha1Man5GlcNAc2, Rha2Man6GlcNAc2, Xyl1Rha2Man6-GlcNAc2, Xyl1Rha3Man6GlcNAc2, and Xyl2Rha3Man6-GlcNAc2. On the other hand, oligosaccharides containing mannosyl, xylosyl, rhamnosyl, and ribosyl units were liberated from endo-beta-N-acetylglucosaminidase-resistant glycopeptides upon treatment with N-glycanase. This is the first report on the presence of ribosyl units in eukaryote glycoconjugates, of rhamnosyl residues in asparagine-linked oligosaccharides, and of xylosyl units in high mannose-type compounds.
Merello
S
S
Instituto de Investigaciones Bioquimicas, Fundación Campomar, Buenos Aires, Argentina.
Xavier
M T
MT
Parodi
A J
AJ
D000818:Animals; D001216:Asparagine / Q000737:chemistry*; D002240:Carbohydrate Sequence; D006023:Glycoproteins / Q000737:chemistry; D006596:Hexosaminidases; D006868:Hydrolysis; D008361:Mannosidases; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry*; D012210:Rhamnose / Q000032:analysis*; D012266:Ribose / Q000032:analysis*; D014351:Trypanosomatina / Q000378:metabolism*; D014994:Xylose / Q000032:analysis*; D043323:alpha-Mannosidase
D006023:Glycoproteins; D009844:Oligosaccharides; D012266:Ribose; D001216:Asparagine; D014994:Xylose; D006596:Hexosaminidases; D008361:Mannosidases; D043323:alpha-Mannosidase; D012210:Rhamnose