Glycosidically linked sugar polymers are well known as nutritional and structural molecules,
and it is now clear that they also have essential roles as carriers of biological information.
The constituent sugar residues contain multiple hydroxyl groups capable of forming complex
arrangements of hydrogen bonds. Sugars are often modified with amino, N-acetyl, carboxyl,
phosphate, and sulfate groups, permitting more varied interactions than those achieved with
hydroxyls. Many different sugars occur in nature, and these can be coupled in numerous …