RESUMEN
A proteolytic thermo-alkalophilic, Bacillus stearothermophilus, S-WN 1616B isolated from Wady El-Natroon, Egypt, proved to be very promising with regard to protease[s] formation under extreme thermo- alkalophilic conditions. Thus, the purification process was found to be necessary to find out the unique properties of such kind of enzymes. Accordingly, the enzyme was collected under all optimal conditions of production. Then, it was subjected to a process of purification through a preparation of cell free filtrate, an application of ammonium sulfate precipitation technique, performing dialysis methods, then applying gel-filtration using sephadex column chromatographic technique. This resulted in a partially purified enzyme preparation with specific activities of 1620 units/mg protein/ml corresponding to purification folds of 48.2 times of the origin