Open AccessPorcine submaxillary mucin contains α2→3‐ and α2→6‐linked N ‐acetyl‐ and N ‐glycolyl‐neuraminic acid
Author(s) -
SAVAGE Angela V.,
KOPPEN Piet L.,
SCHIPHORST Wietske E. C. M.,
TRIPPELVITZ Leo A. W.,
HALBEEK Herman,
VLIEGENTHART Johannes F. G.,
EIJNDEN Dirk H.
Publication year - 1986
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1986.tb09948.x
Subject(s) - chemistry , trisaccharide , oligosaccharide , neuraminic acid , mucin , borohydride , sialic acid , molar ratio , nuclear magnetic resonance spectroscopy , stereochemistry , mass spectrometry , chromatography , biochemistry , catalysis
Four acidic trisaccharides have been obtained by alkaline borohydride reductive cleavage (β‐elimination) of a fraction of porcine submaxillary mucin precipitating at 60 – 75% ethanol. Their structures have been investigated using the techniques of methylation analysis involving gas‐liquid chromatography/mass spectrometry along with high‐resolution 1 H‐NMR analysis. Two of the four oligosaccharides, B1 – B4, contain N ‐acetylneuraminic acid (NeuAc) while two contain N‐glycolylneuraminic acid (NeuGc). The following structures are proposed for the acidic trisaccharide fraction: (B1) NeuAcα(2→3)Galβ(1→3)GalNAcol, (B2) NeuGcα(2→3)Galβ(1→3)GalNAcol, (B3)Galβ(1→3)[NeuAcα(2→6)]GalNAcol and (B4) Galβ(1→3)[NeuGcα(2→6)]GalNAcol, (GalNAcol = reduced N ‐acetylgalactosamine. These oligosaccharides were present in a molar ratio of 69:22:4:5. Although oligosaccharide B4 has previously been found in porcine submaxillary mucin B1, B2 and B3 have not. Furthermore, oligosaccharide B2 is a novel structure.