Sialic Acid and Related Substances

The Structure of Cyameluric Acid, Hydromelonic Acid and Related Substances.

Over a century ago, in 1835, Leopold Gmelin' prepared the substance tripotassium hydromelonate by heating potassium ferrocyanide with sulfur; he also made other salts of hydromelonic acid, and carried out analyses, which, however, were not sufficiently accurate to lead to correct formulas. He recognized the similarity of the substances to the group of nitrogen compounds discovered and named by ...

Diversity in sialic and polysialic acid residues and related enzymes*

The occurrence of extensive diversity in the family of sialic acids is now well recognized but biological signi®cance of this diversity has been clari®ed only partially. In 1986 we showed natural occurrence of deaminated form of neuraminic acid, 2-keto-3-deoxy-Dglycero-D-galacto-nononic acid (KDN) as a capping residue of polysialyl chain of rainbow trout egg polysialoglycoprotein. Subsequent st...

The role of sialic acid synthases in sialic acid biosynthesis

Introduction The sialic acids comprise a diverse family of nine-carbon keto-sugars, the majority of which are structural derivatives of neuraminic acid (Fig. 1). Neuraminic acid has an amino moiety at the C-5 position, and carboxylate at C-2 which confers negative charge at physiological pH. Whereas unsubstituted neuraminic acid is not known to exist in nature, over 40 substituted variations (c...

Reactions of 6-aminopenicillanic acid with carbohydrates and related substances.

Sialic acid and cell aggregation.

Chick embryo neural retina cells from 7-, 10and 14-day embryos and muscle cells from 9-day embryos, dissociated mechanically or with trypsin, reaggregate at the same initial rate whether treated before and during aggregation with active or inactive iV-acetyl neuraminidase. 7V-acetyl neuraminidase treatment also has no effect on the size or number of aggregates formed over 24 or 48 h of aggregat...