Sugar acids sialic acid

N-Acetylneur-aminic acid Sialic acid (nine C atoms) NeuAc CMP-NeuAc Often the terminal sugar in both N- and 0-linked glycoproteins. Other types of sialic acid are also found, but NeuAc is the major species found in humans. Acetyl groups may also occur as 0-acetyl species as well as N-acetyl. 

Figure 6.3 Synthesis of modified sugars with sialic acid aldolase mutants...

Fig. 19. Cyclodextrins decorated with sugars, including sialic acid and sialyl oligosaccharides. 

Figure 2.19 Sialylation ofN-acetyl lactose by cytidyl monophosphate-N-acetylneuraminic acid using Of 2,3-neuraminic acid transferase as catalyst (upper box). Regeneration of the sugar nucleotide is shown in the lower box. CMP is converted into CTP in two steps using two different kinases. In the final step CMP-A -acetylneuraminic acid is synthesised from CTP and A -acetylneuraminic acid (sialic acid) using the appropriate synthetase. The formed pyrophosphate is converted into inorganic phosphate. Altogether five different enzymes are involved in the process.

Unsubstltuted sugars Amino sugars Desoxy sugars Others Sialic acids Substituents... 

For glycoproteins, the carbohydrate content (neutral sugars, amino sugars, and sialic acids) is determined. In addition, the structure of the carbohydrate chains, the oligosaccharide pattern (antennary profile), and the glycosylation site(s) of the polypeptide chain are analyzed, to the extent possible. 

Ganglioside Complex carbohydrate-rich glycosphingolipids containing three or more monosaccharides esterified to ceramide with at least one of the sugars being A-acetylneuraminic acid (sialic acid). Gangliosides are membrane components found on nerve endings. 

Methanolysis in anhydrous methanolic HCI, followed by N-acetylation of amino sugars and sialic acid, and derivatization of the methyl glycosides formed to volatile trimethylsilyl ethers (TMS) or trifluoracetyl derivatives are widely used (17,18). 

Figure 2.16 Salvage Pathways of Amino-sugars and Sialic Acids in Animals...

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