[Serine protease of Bacillus subtilis R]

Properties of a protease preparation obtained by ethanol precipitation of a concentrate of the culture fluid of Bacillus subtilis R (1 : 4 v/v; 4 degrees C) grown under the conditions of deep cultivation were studied. The use of specific inhibitors, EDTA and phenylmethylsulfonyl fluoride, made it possible to show that the enzyme belongs to the group of serine proteases. The preparation exhibited high stability in alkaline medium and thermostability; it hydrolyzed protein substrates and retained catalytic properties in the presence of a multicomponent detergent system. The preparation is recommended for use in those branches of industry where proteolysis is required and in the production of detergents (as a biological additive).