MYCOLab Ai Logo - gold and army green

Transcriptome analysis of Ochratoxin A (OTA) producing Aspergillus westerdijkiae fc-1 under varying osmotic pressure

Summary

Researchers studied how salt levels affect the production of Ochratoxin A (OTA), a harmful toxin made by a fungus commonly found in foods like coffee and dried meats. Using genetic analysis techniques, they found that different salt concentrations trigger different genes in the fungus, affecting how much toxin it produces. This research helps explain why OTA contamination is worse in high-salt foods and could lead to better ways to prevent food poisoning from this fungus.

Background

Ochratoxin A (OTA) is a toxic secondary metabolite produced by Aspergillus species that contaminates various food products and poses significant health threats to humans and animals. Aspergillus westerdijkiae is a major OTA producer commonly found in beverages, grapes, wheat, coffee beans, and dry pickles. Osmotic pressure from high salt content in foods is known to influence OTA production.

Objective

This study analyzed the transcriptome of Aspergillus westerdijkiae fc-1 strain under varying NaCl concentrations (0, 20, and 100 g/L) using RNA-Seq technology to examine gene transcriptional changes linked to osmotic stress and OTA production. The research aimed to understand correlations between HOG1 expression and OTA biosynthesis genes to develop strategies for preventing OTA contamination in food.

Results

At 20 g/L NaCl, significant changes occurred in carbohydrate metabolism and cellular communication pathways, with OTA biosynthesis genes otaA, otaB, and otaC up-regulated 3.26, 1.99, and 2.06 fold respectively, while HOG1 was down-regulated 78.06%. At 100 g/L NaCl, ion transport and ribosomal pathways were significantly up-regulated, with HOG1 up-regulated 28.32% and all OTA biosynthesis genes showing up-regulation, particularly otaD at 5.72 fold.

Conclusion

The study reveals correlations between HOG1 gene expression and OTA biosynthesis, with distinct metabolic pathway changes at different osmotic pressures. These findings provide insights into molecular mechanisms underlying OTA production and offer a foundation for developing strategies to prevent OTA contamination in food through understanding osmotic stress regulation.
  • Published in:Mycology,
  • Study Type:Molecular Biology Study,
  • Source: PMID: 40415916, DOI: 10.1080/21501203.2024.2408259
Scroll to Top