[Isolation and purification of alkaline ribonuclease from Bacillus intermedius].

The paper describes a method for preparing extracellular alkaline ribonuclease from Bacillus intermedius (EC 3.1.4.23). The method consists of acid treatment of the culture fluid for selective inactivation of the interfering enzymes, concentration of the enzymic protein by ammonium sulfate precipitation, dialysis against water, chromatography on DEAE-cellulose and phosphocellulose in the steady state, rechromatography on a phosphocellulose containing column, desalting and freeze-drying of the end product. Experimental samples of ribonuclease of 92% purity have been thus obtained.