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06:06
Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43
Published on: September 11, 2020
Pherotypes are driving genetic differentiation within Streptococcus pneumoniae.
Margarida Carrolo1, Francisco R Pinto, Jose Melo-Cristino
1Instituto de Microbiologia, Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av, Prof, Egas Moniz, 1649-028 Lisboa, Portugal. mcarrolo@fm.ul.pt
BMC Microbiology
|September 9, 2009
Summary
Two distinct Streptococcus pneumoniae populations exist, defined by pherotypes, which limit gene flow and impact bacterial speciation. This challenges the idea of panmixia in highly recombinogenic bacterial species.
Area of Science:
- Microbiology
- Population Genetics
- Bacterial Speciation
Background:
- Bacterial species boundaries and speciation mechanisms are debated.
- Recombination is a cohesive force preventing bacterial population divergence.
- Streptococcus pneumoniae exhibits high recombination, driven by competence and quorum-sensing.
Purpose of the Study:
- Investigate the distribution and impact of two major pherotypes in Streptococcus pneumoniae.
- Determine the association of pherotypes with serotype, antimicrobial resistance, and genetic lineage.
- Evaluate the influence of pherotypes on horizontal gene transfer dynamics.
Main Methods:
- Multilocus sequence data analysis.
- Population genetic analysis.
- Multilocus infinite allele model simulations.
Main Results:
- Pherotype is a clonal property in pneumococci.
- Two genetically differentiated populations are defined by major pherotypes.
- Pherotypes influence horizontal gene transfer dynamics.
Conclusions:
- Significant limitations to gene flow can occur in bacteria without geographical barriers.
- This departure from panmixia has implications for understanding bacterial adaptation to selective pressures.
- Pneumococcal response to vaccination and antibiotics may be influenced by pherotype-defined populations.
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