When alpha-D-GlcNAc-OC6H4NO2 -p and beta-D-(6-sulfo)-GlcNAc-OC6H4NO2-p (2) were used as substrates, beta-N-acetylhexosaminidase from Aspergillus oryzae transferred the beta-D-(6-sulfo)-GlcNAc(unit from 2 to alpha-D-GlcNAc-OC6H4NO2 -p to afford beta-D-(6-sulfo)-GlcNAc-(1 -> 4)-alpha-D-GlcNAc-OC6H4NO2-p (3) in a yield of 94% based on the amount of donor, 2, added. beta-D-(6-sulfo)-GlcNAc-(1 -> 4)-alpha-D-Glc-OC6H4NO2-p (4) was obtained with alpha-D-Glc-OC6H4NO2 -p as acceptor in a similar manner. With a reaction mixture of 2 and beta-D-GlcNAc-OC6H4NO2-p (1) in a molar ratio of 6:1, the enzyme mediated the transfer of beta-D-GlcNAc from 1 to 2, affording disaccharide beta-D-GlcNAc-(1 -> 4)-beta-(6-sulfo)-D-GlcNAc-OC6H4NO2-p (5) in a yield of 13% based on the amount of 1 added.