Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB
Staphylococcal enterotoxin C (SEC) can cause staphylococcal food poisoning, one of the most prevalent foodborne intoxications. It is produced by Staphylococcus aureus during growth in the food matrix. While the surrounding bacteria in food matrices usually repress the growth of S. aureus, the organi...
| Main Authors: | , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2023-08-01
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| Series: | Journal of Food Protection |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0362028X23068114 |
| _version_ | 1797773617948262400 |
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| author | Danai Etter Céline Jenni Veronica Edwards Mariella Greutmann Tabea Waltenspül Taurai Tasara Sophia Johler |
| author_facet | Danai Etter Céline Jenni Veronica Edwards Mariella Greutmann Tabea Waltenspül Taurai Tasara Sophia Johler |
| author_sort | Danai Etter |
| collection | DOAJ |
| description | Staphylococcal enterotoxin C (SEC) can cause staphylococcal food poisoning, one of the most prevalent foodborne intoxications. It is produced by Staphylococcus aureus during growth in the food matrix. While the surrounding bacteria in food matrices usually repress the growth of S. aureus, the organism possesses a remarkable growth advantage under stressful conditions encountered in many foods. Examples for such food matrices are pastry and bakery products with their high sugar content that lowers water availability. While S. aureus can still grow in these challenging environments, it remains unclear how these conditions affect SEC expression. Here, the influence of 30% glucose on sec mRNA in a qPCR assay and SEC protein expression was investigated for the first time in an ELISA. In addition, regulatory knockout mutants Δagr, ΔsarA, and ΔsigB were generated to investigate regulatory gene elements in glucose stress. In five out of seven strains, glucose stress led to a pronounced decrease in sec mRNA transcription and SEC protein levels were substantially lower under glucose stress. It could be shown that key regulatory elements Δagr, ΔsarA, and ΔsigB in strain SAI48 did not contribute to the pronounced downregulation under glucose stress. Based on these findings, glucose effectively lowers SEC synthesis in the food matrix. However, the mechanism by which it acts on toxin expression and regulatory elements in S. aureus remains unclear. Future studies on other regulatory elements and transcriptomics may shed light on the mechanisms. |
| first_indexed | 2024-03-12T22:09:05Z |
| format | Article |
| id | doaj.art-77278d0ec7044a629ea126bb2c7d4057 |
| institution | Directory Open Access Journal |
| issn | 0362-028X |
| language | English |
| last_indexed | 2024-03-12T22:09:05Z |
| publishDate | 2023-08-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Food Protection |
| spelling | doaj.art-77278d0ec7044a629ea126bb2c7d40572023-07-24T04:10:22ZengElsevierJournal of Food Protection0362-028X2023-08-01868100127Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigBDanai Etter0Céline Jenni1Veronica Edwards2Mariella Greutmann3Tabea Waltenspül4Taurai Tasara5Sophia Johler6Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland; Institute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, SwitzerlandInstitute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, SwitzerlandInstitute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, SwitzerlandInstitute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, SwitzerlandInstitute for Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, SwitzerlandInstitute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, SwitzerlandInstitute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 272, 8057 Zurich, Switzerland; Corresponding author.Staphylococcal enterotoxin C (SEC) can cause staphylococcal food poisoning, one of the most prevalent foodborne intoxications. It is produced by Staphylococcus aureus during growth in the food matrix. While the surrounding bacteria in food matrices usually repress the growth of S. aureus, the organism possesses a remarkable growth advantage under stressful conditions encountered in many foods. Examples for such food matrices are pastry and bakery products with their high sugar content that lowers water availability. While S. aureus can still grow in these challenging environments, it remains unclear how these conditions affect SEC expression. Here, the influence of 30% glucose on sec mRNA in a qPCR assay and SEC protein expression was investigated for the first time in an ELISA. In addition, regulatory knockout mutants Δagr, ΔsarA, and ΔsigB were generated to investigate regulatory gene elements in glucose stress. In five out of seven strains, glucose stress led to a pronounced decrease in sec mRNA transcription and SEC protein levels were substantially lower under glucose stress. It could be shown that key regulatory elements Δagr, ΔsarA, and ΔsigB in strain SAI48 did not contribute to the pronounced downregulation under glucose stress. Based on these findings, glucose effectively lowers SEC synthesis in the food matrix. However, the mechanism by which it acts on toxin expression and regulatory elements in S. aureus remains unclear. Future studies on other regulatory elements and transcriptomics may shed light on the mechanisms.http://www.sciencedirect.com/science/article/pii/S0362028X23068114Foodborne intoxicationsec variantsStaphylococcal food poisoningStress responseSuperantigenVirulence gene regulation |
| spellingShingle | Danai Etter Céline Jenni Veronica Edwards Mariella Greutmann Tabea Waltenspül Taurai Tasara Sophia Johler Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB Journal of Food Protection Foodborne intoxication sec variants Staphylococcal food poisoning Stress response Superantigen Virulence gene regulation |
| title | Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB |
| title_full | Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB |
| title_fullStr | Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB |
| title_full_unstemmed | Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB |
| title_short | Stress Lowers Staphylococcal Enterotoxin C Production Independently of Agr, SarA, and SigB |
| title_sort | stress lowers staphylococcal enterotoxin c production independently of agr sara and sigb |
| topic | Foodborne intoxication sec variants Staphylococcal food poisoning Stress response Superantigen Virulence gene regulation |
| url | http://www.sciencedirect.com/science/article/pii/S0362028X23068114 |
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