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Published on: September 27, 2018
Buruli ulcer: reductive evolution enhances pathogenicity of Mycobacterium ulcerans
Caroline Demangel1, Timothy P Stinear, Stewart T Cole
1Institut Pasteur, UP Pathogénomique Mycobactérienne Intégrée, Paris, France.
Nature Reviews. Microbiology
|December 17, 2008
Summary
Buruli ulcer, caused by Mycobacterium ulcerans, is an emerging infectious disease linked to wetlands and potentially insect transmission. Its evolution from Mycobacterium marinum involved acquiring a toxin-producing plasmid and genetic reduction.
Area of Science:
- Microbiology
- Genomics
- Immunology
- Ecology
Background:
- Buruli ulcer is an emerging infectious disease caused by Mycobacterium ulcerans.
- Mycobacterium ulcerans produces mycolactone, a cytotoxin with immunomodulatory effects.
- The disease is associated with wetlands and insect transmission is increasingly suspected.
Purpose of the Study:
- To review the ecology, microbiology, evolutionary genomics, and immunopathology of Buruli ulcer.
- To provide a comprehensive overview of current knowledge on this emerging disease.
Main Methods:
- Comparative genomic analysis of Mycobacterium ulcerans and Mycobacterium marinum.
- Review of existing literature on the ecology, microbiology, evolution, and immunopathology of Buruli ulcer.
Main Results:
- Mycobacterium ulcerans evolved from Mycobacterium marinum via horizontal gene transfer of a virulence plasmid.
- This plasmid carries genes for mycolactone production, crucial for virulence.
- Reductive evolution followed the acquisition of the virulence plasmid.
Conclusions:
- Understanding the evolutionary genomics and ecology of Mycobacterium ulcerans is key to controlling Buruli ulcer.
- Further research into insect transmission roles and immunopathology is warranted.
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