A double-layer plate method for rapid screening of cell wall-targeting antibiotic producers using a microbial...

Area of Science:

• Microbiology
• Drug Discovery
• Biotechnology

Background:

• Antimicrobial resistance (AMR) necessitates novel antibiotic discovery.
• Conventional methods for identifying antibiotic producers are slow and labor-intensive.
• There is a need for high-throughput screening platforms for environmental microbes.

Purpose of the Study:

• To develop a high-throughput screening platform for identifying bacteria producing cell wall-targeting antibiotics.
• To bypass traditional laborious isolation and purification steps.
• To accelerate the discovery of novel antibiotic producers from environmental samples.

Main Methods:

• Developed a double-layer plate assay integrating a microbial whole-cell biosensor.
• Engineered a sensitive biosensor based on the PghKR two-component system from *Shewanella oneidensis* MR-1.
• Screened soil samples using the platform, identifying colonies with luminescent signals.

Main Results:

• Identified 103 colonies with distinct luminescent signals from soil samples.
• 36 isolates consistently activated the biosensor in a confirmation assay.
• 5 isolates exhibited antibacterial activity against a multidrug-resistant indicator strain.

Conclusions:

• The integrated platform enables rapid, low-cost screening of environmental samples.
• This approach significantly accelerates the discovery of novel antibiotic producers.
• The platform is effective for identifying bacteria producing cell wall-targeting antibiotics.