Major secreted chitinase involved in the degradation of chitin, a component of the cell walls of fungi and exoskeletal elements of some animals (including worms and arthropods) (PubMed:17119968, PubMed:17455791). Plays a role in the morphogenesis and autolysis. Has also significant antifungal activity against various fungal species (PubMed:17119968). Hydrolyzes chitin. Hydrolyzes glycol chitosan very effectively and liberates also reducing sugars from cell debris. Hydrolyzes synthetic substrates 4-nitrophenyl N,N'-diacetyl-beta-D-chitobioside (4NP(GlcNAc)2) and 4-nitrophenyl N,N',N''-triacetyl-beta-D-chitotrioside (4NP(GlcNAc)3), but has no activity against 4-nitrophenyl N-acetyl-beta-D-glucosaminide (4NPGlcNAc) (PubMed:17455791). Random endo-hydrolysis of N-acetyl-beta-D-glucosaminide (1->4)-beta-linkages in chitin and chitodextrins. Highly expressed during the stationary phase and high levels remain in the autolytic stage. Expression is increased when the wild-type mycelia are starved for carbon sources, a condition that induces hyphal autolysis (PubMed:17119968). Significantly up-regulated expression with colloidal chitin and chito-oligomers, namely N-acetyl-D-glucosamine (GlcNAc), N,N'-diacetylchitobiose (GlcNAc)2 and N,N',N''-triacetylchitotriose (GlcNAc)3. Expression is not affected by changes in the levels of reactive oxygen species or in the glutathione-glutathione disulfide redox balance, the changes which are physiological characteristics developing in aging and autolyzing fungal cultures. Down-regulated by the oxidative-stress-generating agent diamide, but not by menadione or hydrogen peroxide (PubMed:17455791). Does not affect germination efficiency nor hyphal growth rate, but considerably reduces the intracellular and extracellular chitinase activities. Belongs to the glycosyl hydrolase 18 family. Chitinase class V subfamily.