Question

What are glycosaminoglycans, and why are sugars good candidates for molecules that fill that role

Answer 1

glycosaminoglycans can be considered as polymers of biomolecules i.e., they are large giant molecules but linear made up of disachharides as its repeating unit (monomer). This disaccharide has two parts:

(a) amino acids: which can be N-acetylglucosamine or N-acetylgalactosamine.

(b) sugar moiety which can be uronic acid ( glucuronic acid or iduronic acid) .

Examples : Hyaluronc acid ( repeating units are alternating beta- D- (1,4)-N- acetylglucosamine and beta-D-(1,3) glucuronic acid

Because the repeating unit has sugar, these molecules are largely carbohydratic in nature.

Sugars are used mainly because of their property that in water, they form gel-like matrix which along with other body proteins form extracellular matri ECM in the body. Only sugars because of their big size and ambient polarity, can serve as good candidates for glycosaminoglycans.

They can also connect to proteins to form proteoglycans.