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Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
DNA methylation in lysogens of pathogenic Burkholderia spp. requires prophage induction and is restricted to excised
1Orion Genomics, 4041 Forest Park, St. Louis, MO 63108, USA.
Journal of Bacteriology
|January 22, 2005
Abstract:
Burkholderia mallei-specific phage PhiE125 encodes DNA methyltransferases in both the lysogenic and replication modules within its genome. Characterization of DNA methylation in recombinant systems, specifically in PhiE125 lysogenic strains of B. mallei and Burkholderia thailandensis, revealed that, upon induction, cytosine methylation was targeted specifically to the phage episome but not the phage provirus or the host chromosome.
Insights
Burkholderia mallei phage PhiE125 DNA methyltransferases target cytosine methylation specifically to the phage episome upon induction. This methylation does not affect the phage provirus or the host chromosome in B. mallei and B. thailandensis.
Area of Science:
- Bacteriophage biology
- Molecular microbiology
- Epigenetics
Background:
- Burkholderia mallei is a Gram-negative bacterium and the causative agent of glanders.
- Bacteriophages, viruses that infect bacteria, play roles in bacterial evolution and can be used in phage therapy.
- DNA methylation is a key epigenetic mechanism regulating gene expression and genome stability.
Purpose of the Study:
- To investigate the DNA methylation activity of Burkholderia mallei-specific phage PhiE125.
- To characterize the target specificity of PhiE125-encoded DNA methyltransferases in recombinant bacterial systems.
Main Methods:
- Recombinant expression of PhiE125 DNA methyltransferases in B. mallei and Burkholderia thailandensis.
- Induction of phage lysogeny and replication modules.
- Analysis of DNA methylation patterns using molecular techniques.
Main Results:
- PhiE125 encodes DNA methyltransferases within its lysogenic and replication modules.
- Upon induction, cytosine methylation was specifically observed on the phage episome.
- No significant methylation was detected on the phage provirus or the host chromosome.
Conclusions:
- The DNA methyltransferases of phage PhiE125 exhibit episome-specific targeting.
- This targeted methylation may play a role in phage replication or maintenance within the host.
- Understanding phage-host interactions is crucial for developing phage-based interventions.
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