DNA modification by methyltransferases

Curr Opin Struct Biol. 1995 Feb;5(1):4-10. doi: 10.1016/0959-440x(95)80003-j.


Enzymatic methylation of DNA plays important roles in both prokaryotes and eukaryotes. Structural study of the HhaI DNA methyltransferase has provided considerable insight into the chemistry of C5-cytosine methylation. The DNA-protein complex reveals a substrate cytosine flipped out of the double helix during the reaction, and a novel two-loop DNA-binding motif used for both sequence recognition and flipping the base. Structural comparison of HhaI C5-cytosine methyltransferase, TaqI N6-adenine methyltransferase, and catechol O-methyltransferase reveals a common catalytic domain structure, which might be universal among S-adenosyl-L-methionine (SAM)-dependent methyltransferases.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Amino Acid Sequence
  • Animals
  • DNA / chemistry*
  • DNA / metabolism*
  • Humans
  • Methyltransferases / chemistry
  • Methyltransferases / pharmacology*
  • Molecular Sequence Data
  • Nucleic Acid Conformation / drug effects*


  • DNA
  • Methyltransferases