Carbohydrate-amino acid linkages Glycosyl linkage

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... 

It is possible that, in this type of glycoprotein, the amino acid sequence of the peptide (specifically, the unusual tripeptide of proline) is involved in signaling the formation of the O-glycosyl type of bridge linkage between the carbohydrate and the protein. Further examples... 

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