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Oral Biofilm Sampling for Microbiome Analysis in Healthy Children
Published on: December 31, 2017
Population structure of Streptococcus oralis
Thuy Do1,2, Keith A Jolley3, Martin C J Maiden3
1Biomedical Research Centre, Guy's and St Thomas' Hospital NHS Foundation Trust, London SE1 9RT, UK.
Microbiology (Reading, England)
|May 9, 2009
Summary
A new multilocus sequence typing (MLST) scheme reveals high diversity in Streptococcus oralis, a common oral bacterium. Analysis indicates significant genetic recombination and a distinct population structure, differentiating it from related species like Streptococcus pseudopneumoniae.
Area of Science:
- Microbiology
- Genetics
- Population Biology
Background:
- Streptococcus oralis is a commensal bacterium in the human oral cavity, known for opportunistic infections.
- Oral streptococci, including S. oralis, display considerable genetic and phenotypic variability.
- Understanding the population structure of S. oralis is crucial for differentiating it from related species and pathogens.
Purpose of the Study:
- To develop and implement a multilocus sequence typing (MLST) scheme for Streptococcus oralis.
- To analyze the population structure, genetic diversity, and recombination patterns within S. oralis.
- To clarify the phylogenetic relationships between S. oralis, Streptococcus mitis, Streptococcus pneumoniae, and Streptococcus pseudopneumoniae.
Main Methods:
- Development of a multilocus sequence typing (MLST) scheme for S. oralis.
- Sequencing of 16S rRNA genes for isolate confirmation.
- Analysis of 113 S. oralis isolates using MLST and ClonalFrame software.
- Comparative analysis with S. pneumoniae, S. mitis, and S. pseudopneumoniae data.
Main Results:
- The developed MLST scheme characterized the S. oralis population as highly diverse.
- Evidence of significant inter- and intra-species recombination was observed, suggesting a clonal complex structure.
- ClonalFrame analysis supported distinct population groupings for the studied species, challenging previous classifications of S. pseudopneumoniae.
- Analysis indicated S. pseudopneumoniae may possess a hybrid nature, explaining discrepancies in phylogenetic clustering.
Conclusions:
- The MLST scheme provides a robust tool for studying S. oralis population genetics.
- S. oralis exhibits substantial genetic diversity and recombination, contributing to its adaptability.
- Phylogenetic analysis using MLST clarifies species boundaries and highlights potential hybridization in related oral streptococci.
- The findings are available on the public MLST database for future research.
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