Streptomyces Research Yields Breakthrough in Antifungal Activity

Strategic Insights -

Research from Northwest A&F University has led to a significant advancement in the antifungal properties of the biocontrol strain Streptomyces pratensis S10. The study, published in Microorganisms, aimed to enhance the antifungal activity of S10 by integrating fermentation optimization and genetic engineering. The research revealed that the fermentation broth of strain S10 can effectively control Fusarium head blight (FHB), caused by Fusarium graminearum. A Plackett-Burman design identified corn flour, yeast extract, and ZnSO4·7H2O as the most critical variables affecting its inhibitory activity and mycelial biomass. The optimized medium improved the mycelial dry weight of S10 from 2.13 g/L to 8.12 g/L, and the antifungal rate against F. graminearum increased from 67.36% to 82.2%.

Key Takeaways:

  • The study involved the isolation of Streptomyces pratensis S10 from tomato leaf mold and its subsequent enhancement of antifungal activity through fermentation optimization and genetic engineering.
  • Single-factor experiments identified seven significant components, including corn flour, yeast extract, NaNO3, CaCO3, K2HPO4, KCl, ZnSO4·7H2O, and MnCl2·4H2O, affecting the inhibitory activity of S10.
  • A Plackett-Burman design revealed that corn flour, yeast extract, and ZnSO4·7H2O were the most critical variables affecting the inhibitory activity and mycelial biomass of S10.
  • The optimized medium improved the mycelial dry weight of S10 from 2.13 g/L to 8.12 g/L and increased the antifungal rate against F. graminearum from 67.36% to 82.2%.
  • Genetic engineering of the key gene tetR led to increased antifungal activity of S10 against F. graminearum.
  • The research established a basis for the large-scale bioactive metabolite secretion of S. pratensis S10, providing a strong foundation for sustainable FHB management in agriculture.

Statistics:

  • The mycelial dry weight of S10 improved from 2.13 g/L to 8.12 g/L.
  • The antifungal rate of F. graminearum increased from 67.36% to 82.2% under the optimized medium.
  • The gene tetR negatively regulates bioactive compound biosynthesis, suggesting its potential role in enhancing antifungal activity.

Sources:

  • Enhancement of Mycelial Growth and Antifungal Activity by Combining Fermentation Optimization and Genetic Engineering in * * Streptomyces pratensis* * S10. Microorganisms, 2025,13(8):1943. (Microorganisms - http://www.mdpi.com/journal/microorganisms).
  • The publisher for Microorganisms is MDPI AG.
  • A free version of this journal article is available at https://doi-org.sdpl.idm.oclc.org/10.3390/microorganisms13081943.