Purification of Crystals Protein by Aqueous Two Phase System fromBacillus thuringiensis Local Isolate

Abstract

The crystals protein of local isolate Bacillus thuringiensis were purified by using
aqueous two phase system method in two steps ; the first 94% of crystals protein and
spores were separated from cell dibbers by using 14% g/ml ammonium sulphate and
4% g/ml of Polyethylene glycol 6000 at pH=7 with separation time of 30 min.
While in the second step, crystals protein were purified from spores by using a
system consisted of 8% g/ml Dextran 60000-90000 and 9% g/ml of Polyethylene
glycol 6000 at pH=7 with separation time of 2.5 h. the a final yield was 70.6% with
purity of 92%