Structural studies on sialylated and sulphated O-glycosidic mannose-linked oligosaccharides in the chondroitin sulphate proteoglycan of brain.
We have previously described the structures of neutral and sialylated O-glycosidic mannose-linked tetrasaccharides and keratan sulphate polysaccharide chains in the chondroitin sulphate proteoglycan of brain. The present paper provides information on a series of related sialylated and/or sulphated tri- to penta-saccharides released by alkaline-borohydride treatment of the proteoglycan glycopeptides. The oligosaccharides were fractionated by ion-exchange chromatography and gel filtration, and their structural properties were studied by methylation analysis and fast-atom-bombardment mass spectrometry. Five fractions containing [35S]sulphate-labelled oligosaccharides were obtained by ion-exchange chromatography, each of which was eluted from Sephadex G-50 as two well-separated peaks. The apparent Mr values of both the large- and small-molecular-size fractions increased with increasing acidity (and sulphate labelling) of the oligosaccharides. The larger-molecular-size fractions contained short mannose-linked keratan sulphate chains of Mr 3000-4500, together with some asparagine-linked oligosaccharides. The smaller tri- to penta-saccharides, of Mr 800-1400, appear to have a common GlcNac(beta 1-3)Manol core, and to contain one to two residues of sialic acid and/or sulphate.
Krusius
T
T
Department of Medical Chemistry, University of Helsinki, Finland.
Reinhold
V N
VN
Margolis
R K
RK
Margolis
R U
RU
D000117:Acetylglucosamine / Q000032:analysis; D000818:Animals; D001923:Brain Chemistry; D002241:Carbohydrates / Q000032:analysis; D011508:Chondroitin Sulfate Proteoglycans; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D005690:Galactose / Q000032:analysis; D013058:Mass Spectrometry; D008970:Molecular Weight; D009844:Oligosaccharides / Q000032:analysis*; D011509:Proteoglycans; D051381:Rats
D002241:Carbohydrates; D011508:Chondroitin Sulfate Proteoglycans; D009844:Oligosaccharides; D011509:Proteoglycans; D000117:Acetylglucosamine; D005690:Galactose