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Updated: May 5, 2026
11:10
High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages
Published on: August 12, 2014
11.7K
Recombination and population structure in Salmonella enterica.
Xavier Didelot1, Rory Bowden, Teresa Street
1Department of Statistics, Oxford University, Oxford, United Kingdom.
Plos Genetics
|August 11, 2011
Summary
Salmonella enterica exhibits significant genetic recombination, challenging its clonal model. Genomic analysis reveals distinct lineages with varying recombination rates and sexual isolation, suggesting incipient speciation.
Area of Science:
- Microbiology
- Evolutionary Biology
- Genomics
Background:
- Salmonella enterica is a significant bacterial pathogen.
- Previously, its population structure was considered clonal based on enzyme electrophoresis.
- Recent genomic studies indicate recombination plays a crucial evolutionary role.
Purpose of the Study:
- To investigate the population structure of Salmonella enterica using genomic data.
- To identify distinct lineages within Salmonella enterica subspecies enterica.
- To analyze the role and patterns of recombination among these lineages.
Main Methods:
- Sequencing approximately 10% of the core genome from 114 Salmonella enterica isolates using resequencing microarrays.
- Applying Structure and ClonalFrame analysis methods to genomic data.
- Assessing genetic differentiation and recombination evidence across identified lineages.
Main Results:
- Five distinct lineages were identified within Salmonella enterica subspecies enterica.
- Significant variation in recombination rates was observed among these lineages.
- Evidence of sexual isolation between lineages was found, with recombination occurring predominantly within lineages.
- One lineage was significantly older than the others, contributing to the subspecies' evolutionary history.
Conclusions:
- Recombination is a key evolutionary force shaping Salmonella enterica populations.
- Ecological structuring and mechanistic barriers contribute to lineage-specific recombination.
- Despite low genetic differentiation, these lineages may represent incipient species, highlighting the dynamic evolution of Salmonella enterica.
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