Partial purification and cleavage specificity of a site-specific endonuclease, SciNI, isolated from Spiroplasma citri

A site-specific endonuclease, SciNI, has been partially purified from the plant pathogen Spiroplasma citri. The enzyme recognizes the sequence 5'-G-C-G-C-3' and cleaves between the first G and C. 3'-C-G-C-G-5' SciNI is an isoschizomer of HhaI, but generates DNA fragments with 5' rather than 3' single-stranded protrusions.