Cytotoxic glutarimide-containing polyketides isolated from Streptomyces sp. JCM 4793
Lin-Fang Tang1,2, Wu-Lai Jihuo1,2, Pei-Dong Shi2
1Faculty of Pharmacy, Yunnan University of TCM, Kunming, Yunnan, 650500, China.
The Journal of Antibiotics
|May 30, 2024
Summary
Three novel glutarimide polyketides were isolated from Streptomyces. The amide-containing compound showed significant antifungal activity, unlike its carboxylic acid form, highlighting the importance of the glutarimide moiety.
Area of Science:
- Natural Product Chemistry
- Microbiology
- Synthetic Biology
Background:
- Glutarimide-containing polyketides are known for their antifungal properties, exemplified by cycloheximide.
- Streptomyces species are a prolific source of diverse bioactive secondary metabolites.
- Understanding structure-activity relationships is crucial for developing new antifungal agents.
Purpose of the Study:
- To isolate and characterize novel polyketides from Streptomyces sp. JCM 4793.
- To evaluate the antifungal activity of the isolated compounds.
- To propose a biosynthetic pathway for the identified polyketides.
Main Methods:
- Isolation and purification of compounds using chromatographic techniques.
- Structural elucidation through spectroscopic methods (NMR, MS).
- Antifungal activity assays against various fungal strains.
Main Results:
- Three new polyketides, 12-amidestreptimidone (1), 12-carboxylstreptimidone (2), and a glutarimide-lacking compound (3), were identified.
- Compound 1 (amide) exhibited significant antifungal activity.
- Compound 2 (carboxylic acid) showed reduced activity compared to compound 1, and compound 3 was inactive.
Conclusions:
- The glutarimide moiety, particularly in its amide form, is critical for potent antifungal activity.
- The findings contribute to the understanding of glutarimide polyketide biosynthesis and structure-activity relationships.
- This study identifies potential leads for the development of new antifungal therapeutics.
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