Enhancement of Anti-MRSA Activity in Endophytic Streptomyces drozdowiczii Ca2- 5 Through OSMAC and Light-Regime Optimization
| Author | Maryam Beiranvand | en |
| Author | Saeid Afshar | en |
| Author | Hashemi Shahraki Abdolrazagh | en |
| Author | Sajad Yaghoubi | en |
| Author | Hadi Samadian | en |
| Orcid | Maryam Beiranvand [0009-0005-3820-2331] | en |
| Orcid | Saeid Afshar [0000-0001-5136-4259] | en |
| Orcid | Hashemi Shahraki Abdolrazagh [0000-0003-1852-194X] | en |
| Orcid | Sajad Yaghoubi [0000-0002-4729-147X] | en |
| Orcid | Hadi Samadian [0000-0002-2478-5709] | en |
| Issued Date | 2026-06-30 | en |
| Abstract | Background: Multidrug-resistant bacteria, particularly methicillin-resistant Staphylococcus aureus (MRSA), pose a major global health threat and cause hundreds of thousands of deaths annually. Endophytic Streptomyces strains are promising sources of bioactive metabolites; however, many of their biosynthetic gene clusters remain silent under standard laboratory conditions. Objectives: This study aimed to activate silent biosynthetic pathways in an endophytic Streptomyces isolate using the one strain–many compounds (OSMAC) strategy to enhance the production of metabolites with anti-MRSA activity. Methods: An endophytic Streptomyces strain was isolated from medicinal plants in Iran. The OSMAC approach was applied by systematically varying key culture parameters, including nutrient composition, pH, aeration, incubation time, and the physicochemical conditions of the medium. Light regimes were also optimized to better simulate the bacterium’s natural habitat. The antibacterial activity of the extracts was evaluated against MRSA ATCC 43300 using the standard agar well diffusion method. Results: Optimization of culture conditions significantly increased the production of secondary metabolites with potent anti-MRSA activity. The largest inhibition zones were achieved under specific combinations of nutrient limitation, a slightly acidic pH, and defined light exposure, compared with standard laboratory conditions. Conclusions: This study highlights the OSMAC strategy as an effective and cost-efficient method for activating silent biosynthetic pathways in endophytic Streptomyces by manipulating culture conditions. The optimized approach provides a valuable framework for discovering novel anti-MRSA compounds from actinobacteria. | en |
| DOI | https://doi.org/10.5812/jjm-172325 | en |
| URI | https://brieflands.com/journals/jjm/articles/172325 | en |
| Keyword | Streptomyces | en |
| Keyword | MRSA | en |
| Keyword | OSMAC Strategy | en |
| Keyword | Phenotypic Screening | en |
| Keyword | Bioactivity Enhancement | en |
| Publisher | Brieflands | en |
| Title | Enhancement of Anti-MRSA Activity in Endophytic <i>Streptomyces drozdowiczii</i> Ca2- 5 Through OSMAC and Light-Regime Optimization | en |
| Type | Research Article | en |