Characterization of the Polysaccharide and Protein Composition of Neurospora crassa Conidium, Perithecium, and Ascospore Cell Walls.

We carried out carbohydrate composition and carbohydrate linkage analyses on Neurospora crassa cell walls from vegetative hyphae, conidia (asexual spores), perithecia (female mating structures), and ascospores (sexual spores). We show that the composition and structure of the cell wall undergo dramatic changes during the N. crassa life cycle. All the cell walls contain β-1,3-glucan and mixed β-1,3-/β-1,4-glucan (lichenin). The conidia cell walls and perithecia cell walls also contain α-1,3-glucan. β-1,3-glucan was the most abundant polysaccharide in the vegetative hyphae cell walls and mixed β-1,3-/β-1,4-glucan was the most abundant polysaccharide in the perithecia and ascospore cell walls. Chitin was a major polysaccharide in the ascospore cell walls. Ascospore and perithecia cell walls also contained melanin as a structural element. We conclude that the composition and structure of the cell wall changes dramatically as cells proceed through the various stages of the N. crassa life cycle.