EC 3.2.1.20 From yeast. Electrophoretically homogeneous. Ammonium sulphate suspension. Specific activity: > 80 U/mg (40°C, pH 7.0, maltose as substrate). Contaminants: α-amylase < 0.001%; ?-glucosidase < 0.001%. Store at 4°C. Stable for > 4 years at 4°C.