Purification and characterization of DNA methyltransferases fromNeisseria gonorrhoeae

Abstract
Three DNA methyltransferases, M NgoAI, and M NgoBI and M NgoBII, free of any nuclease activities were isolated from Neisseria gonorrhoeae strains WR220 and MUG116 respectively. M NgoAI recognizes the sequence 5′ GGCC 3′ and methylates the first 5′ cytosine on both strands. M NgoBI and M.NgoBII recognize 5′ TCACC 3′ and 5′ GTAN5CTC 3′ and 5′ GTAN5CTC 3′ respectively. M NgoBII methylates cytosine on only one strand to produce 5′ GTAN5mCTC 3′.