A N-Acetyl-β-D-glucosaminidase (NAGase) was purified from the integument of cabbage butterfly (Pieris rapae) by extraction with 50 mmol/L of sodium phosphate buffer (PBS, pH 6.8) containing 0.1 M NaCl and ammonium sulfate fractionation, then chromatography on Sephadex G-200 and Econo-Pac CHT-Пcolumn. The purified enzyme was a single band on polyacrylamide gel electrophoresis and the specific activity was determined to be 8715 U/mg. The molecular weight of whole enzyme was measured to be 106.0 kD...