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Modulation of Staphylococcus aureus spreading by water
Mei-Hui Lin1,2,3, Wan-Ju Ke3,4, Chao-Chin Liu1
1Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang-Gung University, Taoyuan, 333, Taiwan.
Scientific Reports
|April 30, 2016
Summary
Staphylococcus aureus spreads by extracting water and floating on the medium surface. This triggers biosurfactant production, weakening surface tension and enabling rapid colony spreading.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Cellular Biology
Background:
- Staphylococcus aureus exhibits rapid colony spreading on surfaces, a phenomenon crucial for infection but mechanistically unclear.
- Understanding bacterial spreading mechanisms is vital for controlling S. aureus infections.
Purpose of the Study:
- To elucidate the underlying mechanisms of Staphylococcus aureus colony spreading.
- To investigate the role of water extraction, bacterial flotation, and biosurfactant production in spreading.
Main Methods:
- Culturing S. aureus and mutant strains on Tryptic Soy Agarose (TSA) medium.
- Utilizing phase contrast and confocal microscopy to observe bacterial behavior.
- Analyzing the role of quorum sensing and biosurfactant (PSM) synthesis.
Main Results:
- S. aureus was observed to extract water from the medium and float on the surface within hours of inoculation.
- Increased bacterial density triggered quorum sensing, leading to the production of phenolic-soluble modulins (PSMs).
- PSMs reduced water surface tension, causing water to flood the medium and facilitate rapid bacterial spread.
Conclusions:
- Staphylococcus aureus employs a unique water-extraction and flotation strategy for colony spreading.
- Quorum sensing-mediated PSM production is essential for weakening surface tension and enabling rapid spread.
- This mechanism explains flagellar-motor-independent spreading, crucial for understanding S. aureus pathogenesis.
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