N-linked oligosaccharides structure

Fig. 2. Generalized structure of N-linked oligosaccharide of the pituitary glycoprotein hormones. SO = sulfate, GIcNAc = N — acetylglucosamine, GalNAc = N — acetylgalactosamine, Man = mannose, Fuc = fucose, SA = sialic (neuraminic) acid.

Mechref, Y., Chen, P, and Novotny, M. V., Structural characterization of the N-linked oligosaccharides in bile salt-stimulated lipase originated from human breast milk, Glycobiology, 9, 227, 1999. 

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. 

Calculations were performed for the disaccharide Mana(l-3)Man0 (see Figure 1 for the structure) which is one of the key linkages in the N-linked oligosaccharide family of structures. 

Figure 4-21 Stereoscopic view of an N-linked oligosaccharide whose structure has been deduced by two-dimensional NMR spectroscopy and energy calculations. This is one of a range of allowed conformations. From Homans et al.257...

NMR measurements to deduce conformations of sugar rings, three-dimensional structures, and the degree of conformational flexibility in various parts of N-linked oligosaccharides (Fig. 4-21). Measurement of C-O-C -C spin-coulping constants is also of value.270 Use of multidimensional NMR has permitted analysis of mixtures of cellulose oligosaccharides.269... 

Figure 20-7 Steps in trimming of the oligosaccharide precursor and synthesis of complex N-linked oligosaccharides of mammalian glycoproteins. Sites of action of several inhibitors are shown. Abbrevations M, mannosyl, Gn, N-acetylglucosaminyl, G, glucosyl residues. Structures of several inhibitors are shown.

J. P. Carver. Site-directed processing of N-linked oligosaccharides the role of three-dimensional structure... 

Figure 22. Proposed structure of N-linked oligosaccharide of the fraction 11-C from A. saitoi acid...

The complex N-linked oligosaccharide contains the j8-Man-di-A-acetylchitobiose (Man-/3-l,4-Glc N Ac-/3-l,4-Glc N Ac-Asn) core structure and also consists of a variable number of outer chains containing sialic acid (sial), galactose (Gal) and fu-cose (fuc) residues linked to the core. Usually, 2a-mannose (Man) residues are at-... 

Although a monoclonal antibody is considered to consist of a single molecule, in reality this is not the most frequent case. Due to posttranslatorial modification, especially glycosylation,12,13 a family of molecules with identical aminoacid backbone, but different carbohydrate composition, is generated.14,15 The possible structure of N-linked oligosaccharides of the complex types is shown in Fig. 3. 

FIGURE 3 Structure of an N-linked oligosaccharide of the complex type occurring in human IgG. The bold typed saccharides constitute the conservative structure, all others are optional. 

Ethier M, Saba JA, Ens W, Standing KG, Perreault H. Automated structural assignment of derivatized complex N-linked oligosaccharides from tandem mass spectra. Rapid Commun. Mass Spectrom. 2002 16 1743-1754. 

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