A New High-Throughput Screening Method to Detect Antimicrobial Volatiles from Metagenomic Clone Libraries

Area of Science:

• Microbiology and Biotechnology
• Natural Product Discovery
• Antimicrobial Resistance Research

Background:

• Increasing antimicrobial resistance necessitates novel therapeutic agents for medicine and agriculture.
• Microbial volatile organic compounds (VOCs) represent a promising, yet underexplored, source of antimicrobials.
• VOCs' properties, including high vapor pressure, are suitable for applications like biofumigation and surface sterilization.

Purpose of the Study:

• To adapt the Two Clamp VOCs Assay (TCVA) into a high-throughput screening method (htTCVA).
• To detect novel antifungal VOCs from metagenomic libraries.
• To demonstrate the feasibility and robustness of the htTCVA for discovering new bioactive compounds.

Main Methods:

• Adaptation of the TCVA to a high-throughput format (htTCVA).
• Screening of a moss metagenomic library against *Fusarium culmorum* using the htTCVA.
• In vitro testing of identified VOCs for antifungal activity against fungal mycelium and spores.

Main Results:

• The htTCVA successfully identified five clones exhibiting antifungal activity against *Fusarium culmorum*.
• Inhibition of mycelial growth reached up to 8%, and spore inhibition up to 30% from the clones.
• Purified VOCs from these clones demonstrated potent in vitro antifungal activity, achieving up to 100% inhibition.

Conclusions:

• The htTCVA is a robust and feasible platform for discovering novel antifungal VOCs from environmental sources.
• This method provides access to unexplored microbial biosynthetic pathways and their secondary metabolites.
• The identified VOCs show significant potential as new antimicrobial agents to combat resistance.