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Updated: Jun 16, 2026
12:06
Generation of a Gene-disrupted Streptococcus mutans Strain Without Gene Cloning
Published on: October 23, 2017
Generation of diversity in Streptococcus mutans genes demonstrated by MLST
Thuy Do1, Steven C Gilbert, Douglas Clark
1Infection Research Group, Dental Institute, King's College London, London, United Kingdom.
Plos One
|February 9, 2010
Summary
Streptococcus mutans, a key bacterium in dental caries, shows low genetic diversity, suggesting it
Area of Science:
- Microbiology and Genetics
- Oral Health and Epidemiology
Background:
- Streptococcus mutans is an oral bacterium linked to dental caries initiation and progression.
- Understanding the genetic diversity and population structure of S. mutans is crucial for caries research.
Purpose of the Study:
- To investigate the genetic diversity and population structure of Streptococcus mutans using Multi-Locus Sequence Typing (MLST).
- To compare the effectiveness of using housekeeping genes versus housekeeping and virulence genes for MLST analysis.
- To explore potential associations between genetic profiles, serotypes, geographical origin, and caries activity.
Main Methods:
- Examined 135 Streptococcus mutans strains using two MLST schemes: 6 housekeeping genes or 6 housekeeping plus 2 virulence genes.
- Analyzed nucleotide diversity, recombination rates, and constructed phylogenetic trees.
- Utilized ClonalFrame analysis to infer population structure and evolutionary history.
Main Results:
- Low nucleotide diversity was observed across all loci, with virulence genes showing slightly higher diversity.
- MLST analysis defined 121-122 sequence types, but phylogenetic trees showed significant incongruence.
- No evidence of a clonal structure, geographical distribution, or association of specific clusters with caries was found.
Conclusions:
- The overall low genetic diversity suggests Streptococcus mutans may be a recently emerged species.
- Intra-species recombination plays a significant role in generating genotypic diversity.
- Current MLST schemes do not reveal strong population structure or links to caries activity or geographical origin.
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