O-linked oligosaccharides structure

Gemmill, T.R. and Trimble, R.B. (1999) Overview of N- and O-linked oligosaccharide structures found in various yeast species. Biochimica et Biophysica Acta, 1426 (2), 227-237. 

The strategy used to perform the PMP oligosaccharide profile analysis, with the use of bovine fetuin as a model system, is given in Scheme 1. Bovine fetuin, a major glycoprotein in fetal calf serum, has been widely used as a model for the study of glycoprotein structure. This glycoprotein contains both N- and O-linked oligosaccharides and detailed structural information is available (9-11). 

N.G. Karlsson, B.L. Schulz, N.H. Packer, Structural determination of neutral O-linked oligosaccharide alditols by negative-ion LC-ESI-MS", J. Am. Soc. Mass Spectrom., 15 (2004)659. 

The structures of the O-linked oligosaccharides have been elucidated for the mucins of the insect stages of the parasite. Both epimastigote and trypomastigote... 

R406 M. Kitagawa, K. Yamashina, S. Tojyo and D. Ulam-Orgikh, In Search for Molecules which Calculate Quantum Mechanically , Mem. Inst. Sci. Ind. Res., Osaka Univ., 2000, 57, 96 R407 A. Klein, G. Strecker, G. Lamblin and P. Roussel, Structural Analysis of Mucin - Type O - Linked Oligosaccharides , Methods Mol. Biol. (Totowa, N.J.), 2000,125,191... 

No complete structure has been determined for this type of O-linked oligosaccharide in Dictyostelium. These carbohydrate chains are resistant to 3-elimination, suggesting that they are not the standard type of HexNAco/pThr/Ser linkage. This type of modification has been defined by a panel of monoclonal antibodies. Reactivity to this antibody is lost in a series of mutant strains which are collectively said to be mutated at the modB locus. 

Plasminogen is the precursor of the serine protease plasmin which is involved in dissolution of fibrin clots and, hence, in removal of thrombi. The plasma concentration is about 12mg/100ml and the molecular mass 81 kDa. It contains 17.1% carbohydrate on two sites, one N-linked and one O-linked oligosaccharide. A variant is also known that is only 0-glycosylated. The structures of the oligosaccharides have been determined [71-73], and are shown in Fig. 11. 

There does not, however, appear to be any major difference in GAG structure between the AF and NP in the same disk. The GAG-attachment region also possesses sites for the attachment of O-linked oligosaccharides, which may represent potential attachment sites for KS substitution (27). However, at least in the human, such substitution appears to be confined to the KS-attachment domain. The KS-attachment domain is devoid of CS, and the CS domains are devoid of KS (28). KS may also be present within the G1 region, the IGD and the G2 region, attached to either O-linked or A-linked ohgosaccharides (29). 

Figure 13.4 Possible biosynthetic sequence for O-linked oligosaccharides. The sequential addition of monosaccharide units for the O-linked oligosaccharide synthesis is exemplified for some core structures with an initial N-acetylglucosamine residue. Glycosylation may continue with stepwise addition of Gal, GlcNAc, Fuc and Sia. The linear codes (GNb3/6 for 1,3/6-linkages of P-N-acetylglucosamine and Ab3 for 1,3-linkage of P-galactose) are used...

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