The Structure of the Fungal Cell Wall

Function

• The cell wall maintains the shape of the cell, giving it tensile strength providing protection from extra-cellular stress and ultra-violet light. The wall is semi-permeable, retaining water while protecting the cell from high osmotic water pressure. The wall acts as a filter, keeping out large, dangerous molecules.

Composition

• The primary structural components of the fungal cell wall are: linked polymers of chitin and glucan microfibrils with chitosan polymers made of glucosamine. The surface of the cell wall is composed of antigenic glycoproteins, agglutinans and adhesion compounds. The wall matrix contains gel-like mannoproteins, polysaccharides and melanin pigments providing coloration.

Structure

• Fungal cell walls enclose the cell plasma membrane and consist of three separate layers. The lower and middle glucans layers and outer glycoprotein layers are interwoven fibrillar polymers held together by covalent bonds. Chitin polymer chains are present throughout the cell wall, helping to maintain its structural morphology.