Protein-carbohydrate linkages

Glycoproteins or mucoproieins. Compounds of proteins with carbohydrates. All glycoproteins contain a hexosamine and usually sulphate, ethanoate and glucuronic acid. The carbohydrate-protein linkages are, in some cases covalent and in others of the salt type. Aqueous solutions of glycoproteins are extremely viscous. 

V. Structural Analysis of Glycopeptides and Glycoproteins Containing Unusual Carbohydrate-Protein Linkages... 

As mentioned in the Introduction, a variety of unusual carbohydrate -protein linkages is found in Nature. These may be placed in several categories (i) carbohydrates O-glycosylated to jff-hydroxy amino acids (ii) carbohydrates S-glycosylated to cysteine (Hi) carbohydrates N-gly-cosylated to the N-terminal amino group of the protein or (iv) in some... 

A linkage involving 4-hydroxy-L-proline and L-arabinose has been detected in glycoproteins of plant origin, and it is also possible that L-cys-teine is part of a carbohydrate-protein linkage. Of the types of linkages just mentioned, which have been extensively discussed in reviews,2-9 only the first three have been the subject of synthetic studies, and it is this aspect of the work that will be discussed in the present Chapter. 

Lindberg and associates103 105 applied the Koenigs - Knorr procedure to the synthesis, from 138 and 139, of 3-0-/ -D-xylopyranosyl-L-serine103 (140), which constitutes the carbohydrate-protein linkage in such pro-... 

The Amino Acid and Carbohydrate Residues in Carbohydrate-Protein Linkages of Mammalian Origin ... 

These conformations were subjected to a combined MD/EM refinement using the NOESY derived constraints as pseudoenergy functions. Families of conformations for the whole molecule were then constructed from the structures derived for each linkage. This procedure was demonstrated on a fragment from the carbohydrate-protein linkage region of connective tissue proteoglycans. 

We will illustrate our methodology using 0-3-D-galactopyranosyl -(1->4) 0-3 D-xylopyranosyl-(1->0)-L-serine (GXS), a fragment from the carbohydrate-protein linkage region of xylose/serine linked proteoglycans. 

The carbohydrate-protein linkages of chondroitin sulfate (CS) and dermatan sulfate (DS) in collagen-associated PGs, have10,11 the general struc-... 

Jones, J.K.N., Perry, M.B., Shelton, B., and Walton, D.T. (1961) Carbohydrate-protein linkage in glycoproteins. I. Syntheses of some model substituted amides and a (2-amino-2-deoxy-D-glucosyl)-L-serine. Can. J. Chem. 39, 1005-1016. 

Marks, G. and Neuberger, A. (1961) Synthetic studies relating to the carbohydrate-protein linkage in egg albumin. J. Am. Chem. Soc. 958,4872-4879. 

MOLECULAR STRUCTURE OF THE CARBOHYDRATE-PROTEIN LINKAGE REGION FRAGMENTS FROM CONNECTIVE-TISSUE PROTEOGLYCANS... 

VIH. Structural Studies on the Carbohydrate-Protein Linkage Region. 215... 

X. Biosynthesis of Carbohydrate-Protein Linkage-Region Oligosaccharides. 228... 

Oligosaccharide Fragments Isolated from the Carbohydrate-Protein Linkage-Region of Dermatan Sulfate Proteoglycans 1... 

Yamada S, Oyama M, Yuki Y, Kato K, Sugahara K. The uniform galactose 4-sulfate structure in the carbohydrate-protein linkage region of human urinary trypsin inhibitor. Eur J Biochem 1995 233 687-693. 

The Carbohydrate-Protein Linkage in Glycoproteins. Part I. The Syntheses of Some Model Substituted Amides and an L-Seryl-D-glucosaminide, J. K. N. Jones, M. B. Perry, B. Shelton, and D. J. Walton, Can.. Chem., 39 (1961) 1005-1016. 

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