The major surface XXXX of the @entity12047 cyst: mucin-type O-glycans decorated by novel @entity3649 -based structures.

@entity1 @entity3954 @entity9928 @entity1735 @entity3649 @entity12047 @entity2328 @entity3363
The cestodes constitute important but understudied @entity1 and veterinary parasites. Their surfaces are rich in @entity3363 , on which very little structural information is available. The tissue-dwelling larva (hydatid cyst) of the cestode @entity12047 is outwardly protected by a massive layer of @entity1735 -rich extracellular matrix, termed the laminated layer. The @entity9928 composition of this layer suggests that its major @entity1735 components are exclusively mucin-type O-glycans. We have purified these glycans after their release from the crude laminated layer and obtained by MS and NMR the complete structure of 10 of the most abundant components. The structures, between two and six residues in length, encompass a limited number of biosynthetic motifs. The mucin cores 1 and 2 are either nondecorated or elongated by a chain of Galpbeta1-3 residues. This chain can be capped by a single Galpalpha1-4 residue, such capping becoming more dominant with increasing chain size. In addition, the core 2 @entity3954 residue is in cases substituted with the disaccharide Galpalpha1-4Galpbeta1-4, giving rise to the blood P(1)-antigen motif. Larger, also related, glycans exist, reaching at least 18 residues in size. The glycans described are related but larger than those previously described from an @entity2328 mucin [Hulsmeier, A. J., et al. (2002) J. Biol. Chem. 277, 5742-5748]. Our results reveal that the @entity12047 cyst exposes to the host only a few different major @entity1735 motifs. These motifs are composed essentially of @entity3649 units and include the elongation by (Galpbeta1-3)(n) and the capping by Galpalpha1-4, novel in animal mucin-type O-glycans.
