part_of part of has part has_part has part N-acetylmuramic acid N-acetylglucosamine cell wall peptidoglycan-based cell wall A protective structure outside the cytoplasmic membrane composed of peptidoglycan (also known as murein), a molecule made up of a glycan (sugar) backbone of repetitively alternating N-acetylglucosamine and N-acetylmuramic acid with short, attached, cross-linked peptide chains containing unusual amino acids. An example of this component is found in Escherichia coli. GO:0009274 cellular_component envelope murein sacculus peptidoglycan