Term: proteoglycan
https://doi.org/10.1351/goldbook.P04899

Definition:
A subclass of protein in which the carbohydrate units are polysaccharides that contain amino sugars. The protein is glycosylated by one or more (up to about 100) glycosaminoglycans [linear polymers of up to about 200 repeating disaccharide units that consist of a hexosamine (d-glucosamine or d-galactosamine) alternating with a uronic acid (d-glucuronic or l-iduronic) or a neutral sugar (d-galactose)].

Related Terms:
1) polysaccharides (http://doi.org/10.1351/goldbook.P04752).
2) amino sugars (http://doi.org/10.1351/goldbook.A00283).
3) glycosaminoglycans (http://doi.org/10.1351/goldbook.G02659).

Source: PAC, 1988, 60, 1389. 'Nomenclature of glycoproteins, glycopeptides and peptidoglycans (Recommendations 1985)' on page 1391 (https://doi.org/10.1351/pac198860091389)

Citation: 'proteoglycan' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04899

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