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Updated: Aug 12, 2026
05:18
High-Resolution Comparison of Bacterial Conjugation Frequencies
Published on: January 10, 2019
Species differences in plasmid carriage in the Enterobacteriaceae
Miranda Sherley1, David M Gordon, Peter J Collignon
1Division of Botany and Zoology, Australian National University, Acton, ACT 0200, Australia. david.gordon@anu.edu.au
Plasmid
|February 14, 2003
Summary
Bacterial species impact plasmid evolution and maintenance, influencing antibiotic resistance spread. Host factors shape plasmid acquisition and evolution within species, affecting clinical resistance patterns.
Area of Science:
- Microbiology
- Genetics
- Evolutionary Biology
Background:
- Antibiotic resistance is a growing global health concern.
- Plasmids play a crucial role in the spread of antibiotic resistance.
- Understanding plasmid evolution within bacterial hosts is vital.
Purpose of the Study:
- To investigate the influence of bacterial species on plasmid characteristics.
- To determine how host factors affect plasmid number, size, and incompatibility group distribution.
- To explore the implications for the evolution of antibiotic resistance plasmids.
Main Methods:
- Analysis of 223 Enterobacteriaceae isolates from wild mammals.
- Quantification of plasmids per isolate.
- Determination of plasmid size and incompatibility group distribution (N, P, W, FII, A/C).
Main Results:
- Plasmid number, size, and incompatibility group distribution varied significantly across bacterial species.
- These plasmid variables were non-randomly distributed concerning bacterial species.
- Host-cell factors appear to constrain plasmid carriage within bacterial strains.
Conclusions:
- Bacterial species exert selective pressures influencing plasmid evolution and maintenance.
- Host-specific adaptations are likely for acquired resistance plasmids.
- Resistance plasmids may evolve independent lineages within bacterial species, despite shared gene origins.
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