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Identification of Virulence Markers of Mycobacterium abscessus for Intracellular Replication in Phagocytes
Published on: September 27, 2018
Insertion and deletion events that define the pathogen Mycobacterium avium subsp. paratuberculosis
David C Alexander1, Christine Y Turenne, Marcel A Behr
1McGill University Health Centre, Montreal, Quebec H3G 1A4, Canada.
Journal of Bacteriology
|November 26, 2008
Summary
Mycobacterium avium subspecies evolved through gene gain and loss. Mycobacterium avium subsp. paratuberculosis acquired DNA, then lost it, shaping its distinct lineages.
Area of Science:
- Microbiology
- Genomics
- Evolutionary Biology
Background:
- Mycobacterium avium comprises genetically diverse subspecies with shared ancestry.
- Genomic heterogeneity contributes to subspecies-specific traits.
Purpose of the Study:
- To investigate the genomic basis of Mycobacterium avium subspecies divergence.
- To understand the evolutionary pathways leading to Mycobacterium avium subsp. paratuberculosis.
Main Methods:
- Phylogenetic analysis using multilocus sequence analysis.
- Examination of large sequence polymorphisms across M. avium strains.
- Comparative genomics of M. avium subspecies.
Main Results:
- M. avium subsp. hominissuis showed high variability in large sequence polymorphisms.
- M. avium subsp. paratuberculosis strains possess unique genomic insertions.
- M. avium subsp. paratuberculosis evolved via gene acquisition (approx. 125 kb) followed by gene loss (38-90 kb).
Conclusions:
- A biphasic evolutionary model (gene gain then loss) explains M. avium subsp. paratuberculosis emergence.
- This model may apply to the evolution of other pathogenic mycobacteria.
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