Amino sugars definition

Amino-5-hydroxymethyl-2-methylpyrimidine, 268-269 Amino sugars definition, 51... 

Several disaccharides containing one residue of an amino sugar have been synthesized by definitive chemical methods in connection with the study of the oligosaccharides from human milk. Others have only been prepared, as noted, by degradation of natural oligosaccharides. 

The amino sugar inhibition pattern su ested two new lines of inquiry which led to the definition of macrophage cell surface molecules involved in the clearance of apoptotic neutrophils. 

The majority of these substances may be considered unique polypeptides which contain unusual amino acids or amino acids joined in some unusual manner. Antibiotics now definitely known to be in this class are the penicillins (2), gramicidin (2), tyrocidine (1), gramicidin-S 3), bacitracin (4), subtilin (-5), polymyxin (6), aerosporin (7) and others. The penicillins are produced by a mold. The others listed here are produced by related bacteria. Streptomycin is a very important antibiotic therapeutically but it does not belong to the polypeptide class, being a complex amino-sugar derivative. 

By far the majority of carbohydrate material in nature occurs in the form of polysaccharides. By our definition, polysaccharides include not only those substances composed only of glycosidically linked sugar residues but also molecules that contain polymeric saccharide structures linked via covalent bonds to amino acids, peptides, proteins, lipids, and other structures. 

Because of the somewhat ambiguous definitions of D and L, another system of nomendature was devised for asymmetric compounds, and it has largely replaced the old D, L-system since the 1960s. However, the D, L-nomendature is still used for amino adds and sugars. 

The use of d- and L-prefixes is a nomenclature for orientation of atomic structure of sugar and amino acid molecules. It is a structural definition and is not related to the optical properties. 

---