Distribution of O-glycosylhydrolases in marine fungi of the Sea of Japan and the Sea of Okhotsk: Characterization of exocellular N-acetyl-β-D-glucosaminidase of the marine fungus Penicillium canescens

Abstract

The capacity to produce exocellular enmzymes was studied for 92 samples of fungi from various marine habitats in the Sea of Okhotsk (78 strains) and the Sea of Japan (14 strains). Strains producing highly active glycanases and glycosidases were found. Synthesis of O-glycosylhydrolases was stimulated by addition of laminaran to the nutrient medium. Highly purified N-acetyl-beta-D-glucosaminidase was isolated from the marine fungus Penicillium canescens. The molecular weight of the enzyme determined by SDS-Na-electrophoresis was 68 kDa. The enzyme displayed maximum activity at pH 4.5 and temperature 45 degrees C. Inactivation half-time of the enzyme at 50 degrees C was 25 min. N-acetyl-beta-D-glucosaminidase hydrolyzed both beta-glucosaminide and beta-galactosaminide bonds and possessed a high transglycosylazing activity.