Genetic Control of Fungal Cell Wall Autolysis

Abstract

The major structural components of fungal cell walls are usually polysaccharide homopolymers, such as glucans and chitin, with chemical structures simpler than those of bacterial peptidoglycan. However, fungal cell walls are also thick and complex envelopes playing the same role as bacterial cell walls. For a number of years we have been addressing the question of the biological role of fungal autolysins, enzymes that can be recognized biochemically as being capable of degrading components of the producer’s cell wall. The autolytic action of these enzymes on fungal walls has always been envisaged as the controlled hydrolytic modification of the wall polymers in many situations that might require some kind of modification of the wall structure. Therefore fungal autolysins have been proposed as agents that may be critical for fungal morphogenesis, and they must represent basic elements contributing to the dynamics of the wall structure, that involves a series of changes throughout the yeast mitotic cell cycle and apical extension of hyphae, as well as in other processes such as sexual conjugation, meiosis, dimorphism, etc.