Peptidoglycan

Peptidoglycan or murein is a polymer that makes up the cell walls of bacteria. It is made of many sugars (or monosaccharides), and amino acids.
Peptidoglycan is made of chains of sugars. Each chain has N-acetylglucosamine and N-acetylmuramic acid, one after the other. The chains are linked to each other by 4-5 amino acids, and other sugar molecules, such as glycine.