Vertebrates, sialic acids occurrence

Echinoderms constitute a peculiar phylum of invertebrates belonging to the most highly organized animals, the Deuterostomia, including, also, all the phyla of chordates. Among the invertebrates, echinoderms are the richest in glycolipids, and differ from all of the other marine invertebrate phyla in that they contain sialoglycolipids.79 This conforms to the data of Warren, who studied the occurrence of sialic acids in Nature, and found that all of the vertebrates have them, but, of the invertebrates, only the echinoderms practically all of the Protostomia contain no sialic acids.274... 

Monitoring of the levels of total sialic acid and lipid-associated sialic acid in serum is an important diagnostic tool for the detection of precancerous lesions [224], Transition-state analogues derived from sialic acid are potent inhibitors of sialidases from various influenza virus strains, and these have been evaluated clinically as influenza remedies [225], A detailed review of our current knowledge regarding the occurrence, specificity and function of sialic acid-specific lectins, particularly those that occur in viruses, bacteria and non-vertebrate eukaryotes has been recently published [226],... 

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