Abstract:
Alkaline protease enzyme from Bacillus cereus LS2B was successively purified by
three steps procedure including ammonium precipitation, membrane dialysis, and HiTrap
ion exchange chromatography with DEAE Sepharose FF matrix. The best enzyme
concentration was obtained by precipitation using 80% of ammonium sulfate
concentration. The activity of enzyme whereas the highest activity was found in the
enzyme with 100% of protein concentration (without dilution). HiTrap ion exchange
chromatography machine was set at flow rate 1.5 ml min-1. The specific activity of the
crude enzyme, ammonium sulfate, membrane dialysis and HiTrap ion exchange were
observed 0.4 U/mg, 0.5 U/ml, 1, 8 U/mg and 7.2 U mg, respectively. At the step of
purification using HiTrap ion exchange chromatography, the alkaline protease enzyme
has increased the degree of purity 16 fold from the crude enzyme. Furthermore, the
protein yield was decreased from 100% from crude enzyme to 2% by HiTrap ion
exchange purification. The purified enzyme was characterized using SDS-PAGE resulted
in three bands of protein molecules which correspond to 34 kDa, 17 kDa, and 13 kDa
molecular weight.
