Author(s): Saeeda Bano1, Mehreen Lateef1, Samina Iqbal1, Beena Naqvi2 and Lubna Iqbal1
Alpha amylase from Bacillus subtilis KIBGE HAS was partially purified by ultrafiltration and ammonium sulphate precipitation. After partial purification, the specific activity of protein increased to 2813 U/mg with 20.8 fold purification. The enzyme showed activity in the presence of chelating agent (EDTA) and protein denaturing agents like PMSF, Urea, dithiothreitol (DTT) and βmercaptoethanol. The enzyme remained active in the presence of Ethylenediaminetetraacetate (EDTA) which was a chelating agent, although enzyme activity declined to 44% at 10 mM concentration. PMSF exerted stimulatory effect on α-amylase and its activity increased up to 3.8 fold at 10 mM concentration. Furthermore, β-mercaptoethanol stimulates catalytic activity up to 3.0 fold at 10 mM concentration. In addition, DTT at 1 mM concentration enhanced α-amylase activity. Similarly urea also caused stimulatory effect on α-amylase activity.