Cell wall The primary cell wall of land plants is composed of the polysaccharides cellulose, hemicelluloses and pectin. Often, other polymers such as lignin, suberin or cutin are anchored to or embedded in plant cell walls. Algae possess cell walls made of glycoproteins and polysaccharides such as carrageenan and agar that are absent from land plants. In bacteria, the cell wall is composed of peptidoglycan. The cell walls of archaea have various compositions, and may be formed of glycoprotein S-layers, pseudopeptidoglycan, or polysaccharides. Fungi possess cell walls made of the N-acetylglucosamine polymer chitin. Unusually, diatoms have a cell wall composed of biogenic
Glucose oxidase niger". Glucose oxidase is synthesized in several species of fungi and insects where it is used to produce hydrogen peroxide which in turn kills bacteria. Notatin, extracted from antibacterial cultures of "Penicillium notatum", was originally named Penicillin A, but was renamed to avoid confusion with penicillin. Notatin was shown to be identical to Penicillin B and glucose oxidase, enzymes extracted from other molds besides "P. notatum"; it is now generally known as glucose oxidase. Early experiments showed that notatin exhibits "in vitro" antibacterial activity (in the presence of glucose) due to hydrogen peroxide formation. "In vivo" tests showed that notatin