The restriction endonuclease PecI from the bacterial strain Paracoccus species 12 recognizes the DNA sequence 5’-TTA^TAA-3’ and is an isoschizomer of PsiI
We identified a bacterial strain, Paracoccus species 12, which produces a novel restriction endonuclease, named PecI. This enzyme recognizes the hexanucleotide palindromic DNA sequence 5’-TTA^TAA-3’ and cleaves it, as indicated by the arrow, generating blunt ends. Thus, PecI is a true isoschizomer of the restriction enzyme PsiI.
A preparation of PecI restriction endonuclease at a concentration of 10,000 U/mL was obtained through a four-step chromatographic purification process. The optimal reaction conditions for the enzyme are SE-buffer 5 (Y) (33 mM Tris-acetate (pH 7.9), 10 mM Mg-acetate, 66 mM K-acetate, 1 mM DTT) and a temperature of 37oC.