A common characteristic of all fungal cells is that they are surrounded by a cell wall. Fungal cell walls are mainly composed of polysaccharides. Two of them, β 1-3 glucan and chitin constitute the common fibrillar skeleton core of the cell wall of all fungal species. This fibrillar core is further decorated with different polysaccharides which composition varies with the fungal species. In the opportunistic human fungal pathogen Aspergillus fumigatus, this amorphous alkali-soluble material is composed of β 1,3 glucan and galactomannan. Cell wall composition and structure is also depending on the morphotype and the conditions of growth. The cell wall of Aspergillus fumigatus is a protective skeleton for this mould and a source of pathogen-associated molecular patterns (PAMPs); both aspects being directly associated to the pathogenic life of the fungus. At least, three of the cell wall polysaccharides are involved in host immune response. Moreover, specific conidial and mycelial cell wall components can be associated with fungal survival in the host. This is specially true for the extracellular matrix recently analysed in A. fumigatus that has been shown to glue the hyphae together and protect the fungus against external stresses. The impact of the cell wall and associated structures during disease establishment will be discussed.
Full conference title:
161st Society for General Microbiology
- SGM 161st (2007)