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Let Me Upgrade You: Impact of Mobile Genetic Elements on Enterococcal Adaptation and Evolution
Cydney N Johnson1, Emma K Sheriff1, Breck A Duerkop1
1Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA.
Journal of Bacteriology
|August 9, 2021
Summary
Mobile genetic elements drive enterococci evolution into multidrug-resistant pathogens. CRISPR-Cas systems in commensal strains limit foreign DNA acquisition, impacting bacterial evolution and ecology.
Area of Science:
- Microbiology
- Bacterial Genetics
- Evolutionary Biology
Background:
- Enterococci are Gram-positive bacteria that exist as both commensals and pathogens.
- Mobile genetic elements (MGEs) like plasmids, transposons, and bacteriophages are key drivers of enterococcal evolution.
- Horizontal gene transfer (HGT) mediated by MGEs has led to multidrug-resistant enterococcal strains, particularly in hospital settings.
Purpose of the Study:
- To review the role of enterococcal mobile genetic elements in bacterial fitness.
- To examine the influence of CRISPR-Cas systems on the acquisition of foreign DNA by enterococci.
- To identify research gaps for a better understanding of enterococcal evolution and ecology.
Main Methods:
- Literature review of studies on enterococcal mobile genetic elements.
- Analysis of the impact of horizontal gene transfer on enterococcal adaptation.
- Examination of CRISPR-Cas systems as a defense mechanism against foreign DNA.
Main Results:
- Mobile genetic elements significantly contribute to the fitness and pathogenicity of enterococci.
- CRISPR-Cas systems in commensal enterococci restrict the uptake of MGEs, limiting HGT.
- The interplay between MGEs and CRISPR-Cas influences the evolutionary trajectory of enterococci.
Conclusions:
- Understanding MGEs and CRISPR-Cas is crucial for comprehending enterococcal evolution.
- Further research into these genetic elements can inform strategies against multidrug-resistant enterococci.
- This review highlights key areas for future investigation into enterococcal ecology and adaptation.
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