Abstract:
Five novel neutral oligosaccharides have been purified from goat
milk using Bio-Gel P-4 and reverse phase C-18 high performance liquid
chromatography. Their structures, as determined by high field H-NMR,
are :
T-V GlcNAc (8 1,6) Gal (6 1,4) Glc
P-II Gal (3 1,4) GlcNAc (3 1,6) Gal ( 3 1,4) Glc
P-I Gal ( 6 1,3)
^GlcNAc (3 1,3) Gal (3 1,4) Glc
Gal (3 1,4) ^
P-III Gal (3 1,4) GlcNAc (3 1,6) Gal (3 1,4) Glc
t
Fuc (a 1,3)
P-IV Gal (3 1,3) GlcNAc (3 1,6) Gal (3 1,4) Glc
t
Fuc (a 1,3)
Structurally, the goat milk oligosaccharides differ markedly from that
of the corresponding oligosaccharides from human milk [Dua, V.K. and
Bush, C.A. (1983) Anal. Biochem. 133, 1-8]. The oligosaccharide P-I
has an interesting structure in the sense that it has two galactose residues
linked via 3 1+3 and 31 + 4 linkage, respectively, to the same GlcNAc
residue at the non-reducing end. The biological functions of these oligosacc
harides are unknown. However, they can serve as substrates for various
glycosyltransferases involved in the synthesis of complex carbohydrates
of milk. They would also be useful in characterization of related structures
from glycolipids and glycoproteins.
