Chitosanase catalyzing the endo-type cleavage of chitosan, the deacylated form of chitin. Chitosanase may be crucial in the degradation of the deacetylated portion of chitin in the fungal cell wall. Chitoolisaccharides produced by the hydrolysis of partially N-acetylated chitosan are known to have many biological activities, including antibacterial activity, immune-enhancing effects, and elicitor activity