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Published on: July 27, 2019
Reverse transcriptase-mediated tropism switching in Bordetella bacteriophage.
Minghsun Liu1, Rajendar Deora, Sergei R Doulatov
1Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Science (New York, N.Y.)
|March 16, 2002
Summary
Bacteriophages generate genetic diversity in Bordetella host species using a novel reverse transcriptase mechanism. This process diversifies the major tropism determinant (mtd) gene, enabling new host receptor interactions.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Host-pathogen interactions frequently rely on mechanisms that foster genetic variability.
- Bacteriophages are viruses that infect bacteria and can influence host evolution.
Purpose of the Study:
- To identify and characterize mechanisms of genetic diversity generation in host-pathogen systems.
- To investigate the role of bacteriophages in shaping tropism for Bordetella species.
Main Methods:
- Identification of temperate bacteriophages infecting Bordetella species.
- Analysis of the major tropism determinant (mtd) gene and its diversity.
- Investigation of the reverse transcriptase-mediated process for nucleotide substitution.
Main Results:
- A group of temperate bacteriophages was found to generate diversity in the mtd gene.
- Tropism switching is mediated by a template-dependent, reverse transcriptase process.
- This mechanism introduces specific nucleotide substitutions within the mtd gene, creating diverse ligand-receptor interactions.
Conclusions:
- Bacteriophages employ a sophisticated mechanism involving reverse transcriptase to generate genetic diversity in the mtd gene.
- This cassette-based system allows for a wide range of potential interactions between phage ligands and host receptors.
- The identified mechanism contributes significantly to the adaptability and evolution of host-pathogen interactions.
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