ISOLATION AND CHARACTERIZATION OF SITE-SPECIFIC ENDONUCLEASE BSP123-IFROM THERMOPHILIC STRAIN BACILLUS SPECIES-123

The preparation of site-specific endonuclease Bsp123 I was isolated an d purified from the thermophilic strain Bacillus species 123. Endonucl ease Bsp123 I recognizes the sequence CGCG and cleaves it in the middl e between nucleotides G and C, producing blunt ends. Thus, Bsp123 I is an isoschizomer of FnuDII. The maximal activity of the enzyme is disp layed at 42 degrees C, pH 8.0, 100 mM NaCl, 10 mM MgCl2.