EXTRACELLULAR CALCIUM-INHIBITED ALPHA-AMYLASE OF BACILLUS-COAGULANS B-49

Extracellular alpha-amylase (EC 3.2.1.1) from Bacillus coagulans B 49 was purified to homogeneity by ion-exchange chromatography and gel fil tration. The optimum pH and temperature for dextrinizing activity were 6-7 and 70-degrees-C and for saccharolytic activity were 7 and 60-deg rees-C, respectively. Calcium inhibited alpha-amylase activity even at low concentrations (10 mm), and most of its activity could be restore d by dialysis against EDTA. Other cations such as Mg2+, Fe2+, and Hg2 also inhibited amylase activity, while Mn2+ exhibited a slight stimul atory effect. The activity of the enzyme was not affected by ethylened iaminetetraacetic acid (EDTA).