uronic

Uronic refers to a class of sugar-derived acids known as uronic acids, which are formed by oxidation of the terminal carbon of a monosaccharide. In hexoses this typically involves oxidation of the primary alcohol at C-6 to a carboxyl group, producing a negatively charged sugar acid at physiological pH. The resulting molecules are monosaccharides with an extra carboxyl group and can adopt pyranose or furanose ring forms as their uronic acids.

Common examples include glucuronic acid (GlcA), galacturonic acid (GalA), and iduronic acid (IdoA). These residues are widely found in glycosaminoglycans such as hyaluronic acid (which contains GlcA and GlcNAc), chondroitin sulfate, heparan sulfate, and dermatan sulfate. Galacturonic acid is a major component of pectin in plant cell walls. The presence of carboxylate groups gives uronic acids a high degree of polarity and negative charge, contributing to the structural properties and interactions of the polysaccharides in which they reside.

Biosynthesis and metabolism involve UDP-sugars. UDP-glucuronic acid, produced from UDP-glucose, serves as a key donor in detoxification reactions in the liver, where glucuronidation attaches glucuronic acid to drugs, bilirubin, hormones, and xenobiotics to enhance solubility and excretion. Uronic acids also play roles in the architecture of the extracellular matrix in animals and in plant cell wall chemistry, influencing polysaccharide structure, hydration, and signaling.