Question

Oligosaccharides are short sugar polymers that can become covalently linked to proteins and lipids through condensation reactions. These modified proteins and lipids are called glycoproteins and glycolipids, respectively. Within a protein, which of the amino acids (shown in Figure Q2-48) is the most probable target for this type of modification?

a) serine
(b) glycine
(c) phenylalanine
(d) methionine

Answer 1

Within a protein, serine is the most likely amino acid to be targeted for glycosylation, resulting in the formation of glycoproteins, due to its side chain that contains a hydroxyl group.

Step-by-step explanation:

Oligosaccharides, which are short polymers of monosaccharides, can become covalently linked to proteins and lipids, forming glycoproteins and glycolipids, respectively.

Within a protein, oligosaccharides are typically linked to the hydroxyl group on serine (serine) or threonine amino acids through a process called O-glycosylation, or to the amide nitrogen on asparagine amino acids through N-glycosylation.

Of the amino acids presented in the question (serine, glycine, phenylalanine, methionine), serine is the most probable target for this type of modification, due to the presence of the hydroxyl group in its side chain which is necessary for the O-glycosylation linkage.