Comparison of chitin content in the apical and distal parts of fungal hyphae in Basidiobolus ranarum, Neurospora crassa and Coprinus sterquilinus

Primary cell wall is synthesized in the growth zone of hyphal apex in fungi and rigidified during maturation along the newly formed hypha. Cross-linki ng of cell-wall components and self-assembly of individual polysaccharide c hains into microfibrils are supposed to be involved in the rigidification p rocess. We determined the relative chitin content in the cell wall of hypha l tips and distal walls of three fungal species and demonstrated a general increase in relative chitin content in mature cell walls. Thus, this increa se can be supposed to raise cell-waif rigidity as the principal role of chi tin in the determination of cell-wall rigidity is beyond doubt.