Hhal methyltransferase flips its target base out of the DNA helix

@article{Klimaauskas1994HhalMF,
  title={Hhal methyltransferase flips its target base out of the DNA helix},
  author={Saulius Klima{\vs}auskas and Sanjay Kumar and Richard J. Roberts and Xiaodong Cheng},
  journal={Cell},
  year={1994},
  volume={76},
  pages={357-369}
}
The crystal structure has been determined at 2.8 A resolution for a chemically-trapped covalent reaction intermediate between the HhaI DNA cytosine-5-methyltransferase, S-adenosyl-L-homocysteine, and a duplex 13-mer DNA oligonucleotide containing methylated 5-fluorocytosine at its target. The DNA is located in a cleft between the two domains of the protein and has the characteristic conformation of B-form DNA, except for a disrupted G-C base pair that contains the target cytosine. The cytosine… Expand
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