Oligosaccharides N-linked

Keratan sulfate 0-Linked oligosaccharide N-Linked oligosaccharide Link proteins... 

Weinstein, J., de Souza-e-Silva, U., and Paulson, J. C., 1982, Sialylation of glycoprotein oligosaccharides N-linked to asparagine, J. Biol. Chem. 257 13845-13853. 

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.

Complex, Hybrid, High-Mannose Are the Three Major Classes of N-Linked Oligosaccharides... 

The Biosynthesis of N-Linked Glycoproteins Involves Dolichol-P-P-Oligosaccharide... 

Figure 47-4. Structures of the major types of asparagine-linked oligosaccharides. The boxed area encloses the pentasaccharide core common to all N-linked glycoproteins. (Reproduced, with permission, from Kornfeld R, Kornfeld S Assembly of asparagine-linked oligosaccharides. Annu Rev Biochem 1985 54 631.)...

Figure 47-5. Schematic diagram of the pentasaccharide core common to all N-linked glycoproteins and to which various outer chains of oligosaccharides may be attached. The sites of action of endoglycosidases F and H are also indicated.

Many of the proteins are glycoproteins (eg, the glyco-phorins) containing 0- or N-linked (or both) oligosaccharide chains iocated on the externai surface of the membrane. 

Takahashi, N., Wada, Y., Awaya, J., Kurono, M., and Tomiya, N., Two-dimensional elution map of GalNAc-containing N-linked oligosaccharides, Anal. Biochem., 208, 96, 1993. 

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. 

Removal of the oligosaccharide chain from the glycoprotein usually involves the use of one of three main methods treatment with NaOH-NaBH4, hydrazinolysis, or proteolysis.34-36 The NaOH-NaBH4 treatment is used to release, somewhat specifically, oligosaccharides O-linked to serine and threonine. Hydrazinolysis is used to break N-linkages, and proteolysis, to isolate glycopeptides. Each method apparently still has some drawbacks. 

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