Pseudopeptidoglycan (also known as
pseudomurein) is a major
cell wall component of some
archaea that differs from
bacterial peptidoglycan in chemical structure, but resembles eubacterial peptidoglycan in morphology, function, and physical structure. The basic components are
N-acetylglucosamine and
N-acetyltalosaminuronic acid (peptidoglycan has
N-acetylmuramic acid instead), which are linked by ß-1,3-glycosidic bonds.
Lysozyme, a host defense mechanism, is ineffective against organisms with pseudopeptidoglycan cell walls. Lysozyme can break ß-1,4-glycosidic bonds to degrade peptidoglycan; however, pseudopeptidoglycan has ß-1,3-glycosidic bonds, rendering lysozyme useless.