Molecular Biology

, Volume 37, Issue 2, pp 260–272 | Cite as

Prokaryotic DNA Methyltransferases: The Structure and the Mechanism of Interaction with DNA

  • E. S. Gromova
  • A. V. Khoroshaev
Article

Abstract

The review considers current views on the function of DNA methyltransferases (MTases) that belong to prokaryotic type II restriction–modification systems. A commonly accepted classification of MTases is described along with their primary and tertiary structures and molecular mechanisms of their specific interaction with DNA (including methylation). MTase inhibitors are also considered. Special emphasis is placed on the flipping of the target heterocyclic base out of the double helix and on the methods employed in its analysis. Base flipping is a fundamentally new type of DNA conformational changes and is also of importance in the case of other DNA-operating enzymes. MTases show unique sequence homology, and are similar in structure of functional centers and in the mechanism of methylation. These data contribute to the understanding of the general biological significance of methylation, since prokaryotic and eukaryotic MTases are structurally and functionally similar.

DNA methyltransferases structure homology mechanism of DNA methylation S-adenosyl L-methionine DNA methyltransferase inhibitors target base flipping prokaryotes 

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Copyright information

© MAIK “Nauka/Interperiodica” 2003

Authors and Affiliations

  • E. S. Gromova
    • 1
  • A. V. Khoroshaev
    • 1
  1. 1.Chemical DepartmentMoscow State UniversityMoscowRussia

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