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Published on: September 8, 2021
Acetic acid increases the phage-encoded enterotoxin A expression in Staphylococcus aureus.
Nina Wallin-Carlquist1, Rong Cao, Dóra Márta
1Applied Microbiology, Lund Institute of Technology, Lund University, Lund, Sweden. Peter.Radstrom@tmb.lth.se.
BMC Microbiology
|May 22, 2010
Summary
Acetic acid increases Staphylococcus aureus enterotoxin A (SEA) production by inducing the sea-encoding prophage, especially at pH 6.0. This links SEA levels to the phage
Area of Science:
- Microbiology
- Food Safety
- Molecular Biology
Background:
- Investigated the impact of acetic acid, a food preservative, on Staphylococcus aureus enterotoxin A (SEA) expression and production.
- Conducted pH-controlled batch cultures at various pH levels (7.0 to 4.5) and performed genomic analysis of sea-carrying S. aureus strains.
Purpose of the Study:
- To determine how acetic acid affects bacteriophage-encoded enterotoxin A (SEA) expression and production in Staphylococcus aureus.
- To analyze genomic variations in the sea gene and its associated temperate phage.
Main Methods:
- pH-controlled batch cultures of S. aureus.
- Analysis of sea mRNA and SEA protein levels.
- Genomic analysis of S. aureus strains and associated phages.
- Prophage induction using mitomycin C.
Main Results:
- SEA expression and production were significantly reduced at pH 5.0 and 4.5.
- Increased sea expression at pH 6.0 and 5.5 correlated with higher intracellular sea gene and extracellular phage copy numbers.
- SEA production was partially linked to prophage induction of the sea-phage.
- Genetic analysis revealed distinct sea phage groups and two sea gene variants.
Conclusions:
- Acetic acid induces the sea-encoding prophage in S. aureus, increasing SEA expression.
- SEA production is linked to the lifecycle of the temperate phage.
- pH and phage genetics influence SEA production in S. aureus.
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