[A new site-specific endonuclease from Bacillus species ST5].

A site-specific endonuclease R.BspST5I has been isolated in a functionally pure state from the thermophilic strain of Bacillus species ST5. The enzyme recognizes sequence 5'-GCATC-3' on the DNA and splits it at a distance of five nucleotides from the 3'-end of the recognition site as well as at distances of nine or ten nucleotides at the complementary filament depending on the hydrolyzed sequence of the DNA. The enzyme is a isomer of endonuclease SfaNI from Streptococcus faecalis ND547.