Restriction endonuclease BamHI and similar proteins
Restriction endonuclease BamHI (EC 18.104.22.168), also termed R.BamHI, or endonuclease BamHI, is a type II restriction enzyme that require only divalent metals (such as Mg2+ or Mn2+) as cofactors to catalyze the hydrolysis of DNA. BamHI recognizes the double-stranded sequence GGATCC and cleaves after G-1. It shows striking resemblance to the structure of EcoRI, but lacks sequence similarity between them. The family also includes a BamHI isoschizomer, OkrAI endonuclease, which recognizes and cleaves the same DNA sequence (TATGGATCCATA) as BamHI. However, OkrAI does not have the equivalent of N- and C-terminal helices of BamHI, and it has higher star activity compared to BamHI.