Том 2025

We identified a bacterial strain, Brevundimonas mongoliensis 53, which produces a new Type II restriction endonuclease, designated BmoI. BmoI recognizes the palindromic heptanucleotide sequence 5’-GG^GWCCC-3’ (W = A or T) and cleaves at the indicated position to generate three-nucleotide 5′ overhangs. BmoI is an isoschizomer of the previously described restriction enzyme SanDI. The producing strain was identified based on morphological and biochemical characteristics and by sequencing a fragment of the 16S rRNA gene. A preparation of BmoI with an activity of 2000 U/ml was obtained using a three-step chromatographic purification workflow. Optimal reaction conditions for BmoI were determined to be SE buffer W (10 mM Tris-HCl, pH 8.5; 10 mM MgCl₂; 100 mM NaCl; 1 mM DTT) and an incubation temperature of 37°C.

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.