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Genetic and Virulent Difference Between Pigmented and Non-pigmented Staphylococcus aureus
Jing Zhang1, Yujuan Suo2, Daofeng Zhang1
1MOST-USDA Joint Research Center for Food Safety, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
Frontiers in Microbiology
|April 19, 2018
Summary
This study investigated Staphylococcus aureus pigment production and virulence. Non-pigmented S. aureus and S. argenteus strains showed similar virulence to pigmented strains in mice, suggesting no significant differences.
Area of Science:
- Microbiology
- Molecular Biology
- Infectious Diseases
Background:
- Staphyloxanthin (STX), a pigment from Staphylococcus aureus, is a potential virulence factor due to antioxidant properties.
- Reduced STX production is linked to decreased virulence, but the virulence of naturally non-pigmented S. aureus is unclear.
Purpose of the Study:
- To compare pigmented and non-pigmented Staphylococcus aureus isolates for genetic and virulence differences.
- To determine if pigment production influences S. aureus virulence.
Main Methods:
- Phenotypic classification of 132 S. aureus isolates based on staphyloxanthin production.
- spa typing, multilocus sequence typing (MLST), virulence factor gene detection, and crtN/crtM gene integrity analysis.
- Murine sepsis model to assess in vivo virulence of selected isolates and S. argenteus strains.
Main Results:
- Pigmented isolates were diverse across 25 sequence types (STs), while non-pigmented isolates clustered in ST20 and ST25.
- Approximately 20% of non-pigmented isolates possessed intact crtN and crtM genes.
- Non-pigmented S. aureus and S. argenteus strains exhibited comparable virulence to pigmented strains in a murine model.
Conclusions:
- Pigment production does not appear to be a reliable indicator of Staphylococcus aureus virulence.
- No significant genetic or virulence disparities were found between pigmented and non-pigmented S. aureus isolates.
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