Purification of thermostable alkaline protease from recombinant e.coli BL21 pLysS 50a Strain

Thermostable alkaline protease which being extracted by using the E.coli BL21 pLysS 50a is purified by using heat treatment method at 70°C for 2, 3, and 4 hours. The enzyme which been purified for the duration of 2 hours has lowest protein content and highest protease activity. The enzyme was fully purified with average of 12.54-fold. Protein profiling, SDS PAGE was carried out to confirm whether the sample is fully purified by observing the bands in order to further confirm the purity level of the protease enzyme with different incubation time heat treatment. The fully purified enzyme has lesser band existed compared to the crude enzyme which act as control. This enzyme can withstand high temperature from 70 to 80°C. This enzyme found to be most stable in pH 7 when in phosphate buffer.