The conformations of oligosaccharides related to the ABH and Lewis human blood group determinants

Abstract

. Can. J. Chem. 58,631 (1980). Nuclear magnetic resonance properties are shown to be in good accord with those that are expected for synthetic oligosaccharides in the conformations which are predicted by hard-sphere molecular modelling and taking into consideration the important contribution by the exa-anomeric effect. The studies involve first a comparison of the PDG~I(IA~)PDGICNAC (Type I) and p~G a l - On montre que les proprietes de rmn sont en accord avec celles attendues pour les oligosaccharides synthetiques selon les conformations prevues par les modeles spheriques rigides et en tenant compte de la contribution importante de l'effet anomkrique eso. Les etudes impliquent en premier lieu une comparaison des structures des disaccharides ~~Gal(1+3)puGlcNAc (type 1) et p~G a l ( 1 4 4 ) P DGIcNAc (type 2) basee principalement sur les donnees de la rmn du I3C et en second lieu I'ttude des relations existant entre les conformations calc~llees et ies parametres de la rmn du lH et du 13C des determinants du groupe sanguin humain qui derivent du noyau disaccharide de type 1. Parmi les structures examinees on trouve le di, tri et tetrasaccharides pour le ABH et les dtterminants antigeniques de Lewis. On note certaines relations immunologiques-conformationnelles.[Traduit par le journal]

Multiple O-Glycoforms on the Spore Coat Protein SP96 in Dictyostelium discoideum

“…8) showed correlation from H-1 to H-2 and H-3 and a weak correlation to H-4 to complete the assignments. The chemical shifts of Fuc were similar to those previously reported (45), while those of GlcNAc were affected by the ␣-1-phosphate. In particular, C-2 and C-5 were shifted ϳ2 ppm upfield by the shielding effect of the phosphate.…”

Syntheses of core chain trisaccharides related to human blood group antigenic determinants

“…The 'H-and 13C-chemical shifts for the glycosides 9 to 12 are presented in ence in these regards (22) and clearly confirm the structural assignments. The 13C chemical shifts are seen to be characteristic of a given disaccharide unit ( P D G~~(~+~) P D G~c N A~, P D G~~(~-+~) P DGlcNAc, ~~G l c N A c ( l + 6 ) f i~G a l , or PDGIcNAc-(1+3)P~Gal).…”

“…These observations support the contention that 13C nmr can play an important role in structural investigation of complex oligosaccharides especially since these appear to be less sensitive to changes in environment. such as the specific interunit chemical shifts which may be observed in the case of IN-chemical shifts (22).…”

Characterisation by mass spectrometry and 500‐MHz proton nuclear magnetic resonance spectroscopy of penta‐ and hexasaccharide chains of human foetal gastrointestinal mucins (meconium glycoproteins)

“…However, this may not be true for branches linked to GalNAcr-SerlThr rather than GalNAcol. The proposed spatial orientation of the periphcral substitutions, GlcNAcml-4 linked to Galpl-4GlcNAcfil-6 in fractions K2(3), K4(2), and K6(3) and Fucal-2 linked to Galpl3GalNAcol in fraction K6(3), suggest that these form relatively globular conformational domains as has been shown for the blood group and related antigens, H, A, B, Lea, Leh, SSEA-1 and their sialylated analogues [lX, 19,22,[28][29][30][31]. This, together with the possible restricted distribution of thc C?lcNAcnl-4Gal sequence and its relative abundance in human foetal gastrointestinal mucins, suggests its potential as an epithelial marker for differentiation stage and neoplastic transformation.…”