Abstract
The complete structure of the complex oligosaccharides of fetuin has been established. The three fractions of complex oligosaccharide which were isolated by ion exchange chromatography following pronase digestion (F-I, F-II, and F-III) had identical molar ratios of sialic acid (Sia), galactose, mannose, and N-acetylglucosamine of 3:3:3:5. A combination of methylation analyses, Smith periodate degradations, and endoglycosidase and exoglycosidase digestions were utilized to establish the structure. Features of this structure not previously established include the presence of 2 residues of α2,3- and 1 residue of α2,6-linked sialic acid and their location relative to the mannose branch points. Also unusual is the presence of an α-linked branch mannose with substituents at positions 2 and 4 which is in turn linked to position 6 of the β-linked, branch mannose. These features result in unexpected resistance to specific exoglycosidases.
| Original language | English |
|---|---|
| Pages (from-to) | 789-795 |
| Number of pages | 7 |
| Journal | Journal of Biological Chemistry |
| Volume | 254 |
| Issue number | 3 |
| State | Published - 1979 |