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Why do most fungal cell walls contain chitin?

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Two Amanita pantherina mushrooms with brown caps covered in white spots grow among moss and fallen leaves. — fungus A pair of panther cap mushrooms (*Amanita pantherina*). Closely related to the death cap mushroom (*Amanita phalloides*), the panther cap is highly poisonous.

In most fungi, chitin and glucan serve as the primary structural components of the cell wall. Chitin is a polysaccharide that provides rigidity and strength to the fungal cell wall, helping to maintain the organism's form and structural integrity.12

While the exact chemical composition of fungal cell walls can vary depending on the species and its stage of development, chitin is favored because it is a chemically stable and tough substance. Its role in fungi is analogous to the function of cellulose in plants; both are complex carbohydrates that offer significant structural support. In some species, chitin can comprise nearly 50 percent of the cell wall's dry weight, demonstrating its importance as a foundational building block for the fungal thallus.13