Selectively hydrolyzes GlcNAcbeta(1->4)GlcNAc (N,N'-diacetylchitobiose) and Gal-NAcbeta(1->4)GlcNAc, but not their C-2 epimers GlcNAcbeta(1->4)ManNAc or Gal-NAcbeta(1->4)ManNAc. However, hydrolyzes both GlcNAcbeta(1->6)GlcNAc and GlcNAcbeta(1->6)ManNAc. Part of the binary chitinolytic system. Involved in hydrolyzation of chitobiose and higher chito-oligomers (produced from cell wall chitin by endochitinases), thus contributing to the formation of germ tubes, fruit-bodies and septa during hyphenation (Probable). Hydrolyzes synthetic substrate p-nitrophenyl-beta-N-acetyl-D-glucosaminide (pNP-GlcNAc). Hydrolyzes synthetic substrate p-nitrophenyl-beta-N-acetyl-D-galactosaminide (pNP-GalNAc). Hydrolyzes chromogenic substrate 4-nitrophenyl-2-acetamido-2-deoxyglucopyranoside