Fungal β-N-acetylhexosaminidases with high β-N-acetylgalactosaminidase activity and their use for synthesis of β-GalNAc-containing oligosaccharides

About 60 fungal strains were tested for production of extracellular β-N-acetylhexosaminidases. A unique β-N-acetylhexosaminidase with the β-GalNAc-ase/β-GlcNAc-ase ratio of 2.3–2.8 was found in the culture filtrates of some strains of Penicillium oxalicum. Addition of 20% (w/v) MgSO4 increased the β-GalNAc-ase/β-GlcNAc-ase ratio to the value of 3.35. Cultivation conditions influence this ratio as well. β-N-Acetylhexosaminidases from P. oxalicum CCF 2430 and Aspergillus oryzae CCF 1066 considerably differing in the GalNAc-ase activity were used for the synthesis of the following structures β-d-GalpNAc-(1→4)-d-GlcpNAc, β-d-GalpNAc-(1→6)-d-GlcpNAc, β-d-GalpNAc-(1→6)-d-GalpNAc, β-d-GalpNAc-(1→4)-α-d-GlcpNAcOAll and β-d-GalpNAc-(1→6)-β-d-Galp-(1→4)-α-d-GlcpNAcOAll to demonstrate the application of these new enzymes.