Characterisation of oligosaccharides released from human‐blood‐group O erythrocyte glycopeptides by the endo‐β‐galactosidase of Bacteroides fragilis

Abstract

Desialylated human blood group 0 erythrocyte glycopeptides were digested with the endo-P-galactosidase of Bacteroides fragilis and the enzyme-released products reduced with NaBH4 and purified by Bio-Gel P-4 chromatography. Three linear and six branched oligosaccharides of poly(N-acetyllactosamine) type, which together accounted for 90% of the oligosaccharide alditols, were characterised by fast-atom-bombardment mass spectrometry and gas-liquid chromatography/mass spectrometry. Linkage and composition data were obtained for the remaining material. The salient findings were (a) the branched oligosaccharide alditols each contained the sequence :and (b) there was no evidence for the terminal branch-point sequence:-GlcNAcPl, :Gal.ol -G~CNACPI' Together these observations indicate that, as with erythrocyte glycolipids described previously [Scudder, P., Hanfland, P., Uemura, K. J. Biol. Chem. 259,, the endo-P-galactosidase of Bacteroides fragilis cannot hydrolyse branch-point P-galactosidic linkages on erythrocyte membrane glycopeptides.Endo-P-galactosidases which hydrolyse internal P-galactosidic linkages in poly(N-acetyllactosamine) sequences can be divided into three groups [l] acting on (a) both sulphated and non-sulphated sequences, (b) sulphated sequences only, and (c)

Structural characterisation of two forms of procyclic acidic repetitive protein expressed by procyclic forms of Trypanosoma brucei

“…The inability of the endo-b-galactosidase to produce a small number of relatively small neutral glycans is thought to be due to the presence of branching points within the polylactosamine domain that are resistant to this enzyme (Scudder et al, 1987). Support for this view was obtained by digestion of a total PARP GPI neutral glycan fraction with a mixture of bovine testes b-galactosidase and jack bean b-hexosaminidase (Figure 7c).…”

Enzymatic in vitro synthesis of I-branches of mammalian polylactosamines: generation of scaffolds for multiple selectin-binding saccharide determinants

“…The modus operandi of both types of I-branching i6GlcNAc transferases was established in our laboratory by identifying the primary products obtained in reactions with the doubly labeled acceptor GlcNAci1-3[ 3 H]Gali1-4GlcNAci1-3[ 14 C]Gali1-4GlcNAc. The branched products were treated with endo-i-galactosidase of Bacteroides fragilis, known to cleave the glycosidic bond of the unreacted galactose, but not that of the branch-bearing galactose [14,15]. Paper chromatography was used to identify and quantify the cleavage products with authentic, enzymatically synthesized oligosaccharides.…”

The Glycosylation of the Influenza A Virus Hemagglutinin by Mammalian Cells

“…This enzyme specifically hydrolyzes the ␤-1,4-linkage in Gal␤4GlcNAc only when it is present within an unbranched polylactosamine sequence, with no outer arm fucosylation (32,33). Bio-Gel P-4 gel filtration chromatography of the glycan pools before and after endo-␤-galactosidase treatment (Fig.…”