0023-6152

AA00697606

24234

Unrefereed

0023-6152

AA00697606

β -Mannosidase, β -N-acetylglucosaminidase, and β -galactosidase were purified from the viscera of apple snails (Pomacea canaliculata) using ammonium sulfate precipitation, hydrophobic chromatography on Butyl Toyopearl 650M, gel filtration on Sephacryl S-300HR, affinity chromatography on fucosyl-Sepharose 4B, and Q-Sepharose column chromatography. Molecular sizes of β-mannosidase, β -N-acetylglucosaminidase, and β-galactosidase were estimated to be approximately 90 kDa, 54 kDa, and 65 kDa by SDS-polyacrylamide gel electrophoresis and to be 450 kDa, 145 kDa, and 66 kDa by gel filtration, respectively. The isoelectric points of β-mannosidase, β-N-acetylglucosaminidase, and β-galactosidase were to be 4.3, 4.5, and 4.9, respectively. The optimum pHs of β -mannosidase, β -N-acetylglucosaminidase, and β-galactosidase toward corresponding p-nitrophenyl(NP)- β-D-glycosides were 5.0, 3.5-6.0, and 3.5-6.0, respectively. The β-mannosidase, β-N-acetylglucosaminidase, and β-galactosidase were stable at pHs of 5.0-S.0, 3.5-9.0, and 3.5-9.0, respectively. The Km values of β-mannosidase, β-N-acetylglucosaminidase, and β-galactosidase toward respective pNP-glycoside at pH 4.0 were calculated as 5.68mM, 39.5mM, and 0.725mM, respectively.