Strategies to decipher silent biosynthetic gene clusters in actinomycetes

Area of Science:

• Microbiology
• Natural Product Chemistry
• Synthetic Biology

Background:

• Actinobacteria are prolific producers of secondary metabolites, crucial for discovering bioactive compounds.
• A significant portion of Actinobacteria's biosynthetic gene clusters (BGCs) remain silent or underexpressed under standard laboratory conditions, limiting natural product discovery.
• Silent BGCs represent a vast, unexplored reservoir of chemical diversity.

Purpose of the Study:

• To review and discuss strategies for activating silent or cryptic biosynthetic gene clusters (BGCs) in Actinobacteria.
• To highlight methods that enhance the discovery of novel bioactive compounds from Actinobacteria.
• To emphasize the role of these strategies in addressing the challenge of antimicrobial resistance (AMR).

Main Methods:

• PCR-Targeted Gene Replacement (PCR-TR)
• Cre-LoxP recombination system
• Transcription factor decoys
• Ribosome engineering
• CRISPR/Cas technologies
• Use of elicitors
• Integration of computational and experimental platforms

Main Results:

• Various molecular and genetic engineering strategies can successfully activate silent BGCs in Actinobacteria.
• Elicitors aid in the identification and activation of cryptic BGCs.
• Combining diverse approaches accelerates the exploration of hidden chemical diversity.
• Successful activation leads to the production of novel secondary metabolites with potential therapeutic applications.

Conclusions:

• Unlocking silent BGCs in Actinobacteria is key to discovering new bioactive natural products.
• Advanced techniques, including CRISPR/Cas and ribosome engineering, are vital for overcoming BGC silencing.
• This approach holds significant promise for developing new antibiotics to combat antimicrobial resistance (AMR).