Peptidoglycan is a polymer of millions of n-acetylglucosamine (nag) and n-acetylmuramic acid (nam) sugars based on glucose molecules linked together in long chains cross-braced with four amino acids that link individual polymer chains together in a chain-link fence pattern. layers of cross-braced nag and nam sheets are stacked vertically and held together by proteins with lipid anchors attached to the cell's cytoplasmic membrane to form a scaffold of sugars and proteins that is able to hold the bacterial cell's shape, even in response to extreme osmotic pressures. how would you expect a microbiology student to be able to describe the composition of peptidoglycan? what is the composition of the peptidoglycan layers found in the cell wall of bacteria?