[Site-specific BcuAI endonuclease from Bacillus cereus A].

A new restriction endonuclease was isolated from the Bacillus cereus BKM B-814 by means of the cell disruption with ultrasonication, ammonium sulfate fractionation of the cell-free extract, and chromatography on DEAE-Sepharose to give about 1400 U of the enzyme per gram of cells. The enzyme revealed the maximum activity at 30-37 degrees C, pH 7.6-8.

[Bsp153AI and BspM39I--new isoschizomers of PvuII restriction enzyme].

New restriction endonucleases, Bsp153AI and BspM39I, were isolated from Bacillus species strains 153A and M39, respectively. The enzymes recognize and cleave the nucleotide sequence [sequence: see text] and are true isoschizomers of restriction endonuclease PvuII.

[New site-specific endonucleases from strains of Bacillus].

In a search for new restriction endonucleases type II, among forty bacterial strains of the Bacillus genus two strains producing site-specific endonucleases have been found. Endonucleases BbvAIII and BspFI, isolated from B. brevis BLM B-677 and B.

[Isolation, purification, and characteristics of the new restriction enzymes BciBI and BciBII, produced by Bacillus circulans].

New site-specific endonucleases BciBI and BciBII have been detected in Bacillus circulans. The enzymes were purified by fractionation of cell-free extract with polyethylene imine and ammonium sulphate (40-80% of saturation) followed by chromatography on DEAE-sepharose, blue-sepharose and phosphocellulose. The endonucleases BciBI and BciBII were separated only at the final step of the purification--by chromatography on the phosphocellulose column.