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.