Editor: Chris Bayliss
Roles of DNA adenine methylation in host–pathogen interactions: mismatch repair, transcriptional regulation, and more
Article first published online: 19 JAN 2009
© 2009 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Reviews
Special Issue: Genome Dynamics
Volume 33, Issue 3, pages 488–503, May 2009
How to Cite
Marinus, M. G. and Casadesus, J. (2009), Roles of DNA adenine methylation in host–pathogen interactions: mismatch repair, transcriptional regulation, and more. FEMS Microbiology Reviews, 33: 488–503. doi: 10.1111/j.1574-6976.2008.00159.x
- Issue published online: 6 APR 2009
- Article first published online: 19 JAN 2009
- Received 13 October 2008; revised 7 December 2008; accepted 8 December 2008.First published online 19 January 2009.
- pathogenic bacteria;
- posttranscriptional regulation
The DNA adenine methyltransferase (Dam methylase) of Gammaproteobacteria and the cell cycle-regulated methyltransferase (CcrM) methylase of Alphaproteobacteria catalyze an identical reaction (methylation of adenosine moieties using S-adenosyl-methionine as a methyl donor) at similar DNA targets (GATC and GANTC, respectively). Dam and CcrM are of independent evolutionary origin. Each may have evolved from an ancestral restriction-modification system that lost its restriction component, leaving an ‘orphan’ methylase devoted solely to epigenetic genome modification. The formation of 6-methyladenine reduces the thermodynamic stability of DNA and changes DNA curvature. As a consequence, the methylation state of specific adenosine moieties can affect DNA–protein interactions. Well-known examples include binding of the replication initiation complex to the methylated oriC, recognition of hemimethylated GATCs in newly replicated DNA by the MutHLS mismatch repair complex, and discrimination of methylation states in promoters and regulatory DNA motifs by RNA polymerase and transcription factors. In recent years, Dam and CcrM have been shown to play roles in host–pathogen interactions. These roles are diverse and have only partially been understood. Especially intriguing is the evidence that Dam methylation regulates virulence genes in Escherichia coli, Salmonella, and Yersinia at the posttranscriptional level.