Sialic acid general functions

Accordingly, they generally contain either N- or O-hnked oligosaccharide chains, or both (Chapter 47). Albumin is the major exception it does not contain sugar residues. The ohgosaccharide chains have various functions (Table 47-2). Removal of terminal sialic acid... 

In addition to the lipid bilayer, enveloped viruses generally have two or more distinct layers of protein that are organized across the membrane. Thus, most viruses have an outer layer of proteins, usually glycoproteins, which are anchored in the membrane as integral membrane proteins. These proteins function to attach the virion to target host cell receptors and facilitate the entry or fusion of the viral membrane with that of the host cell. In addition, some viruses also contain enzymatic activities associated with this outer layer of protein. For example, influenza virus carries with it a neuraminidase that is responsible for cleaving sialic acid residues on host cells. 

Modification of sialic acids already incorporated into glycoconjugates has generally been limited to truncation of the side-chain by mild periodate oxidation to the C-8 or C-7 aldehyde and subsequent reduction to the hydroxy function [10, 76,169]. Lanne et al. [170] have modified the carboxyl group of NeuSAc on the... 

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