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Published on: January 14, 2017
Dissecting antibiotic effects on the cell envelope using bacterial cytological profiling: a phenotypic analysis
Ann-Britt Schäfer1,2, Margareth Sidarta1,2, Ireny Abdelmesseh Nekhala1
1Division of Chemical Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden.
Microbiology Spectrum
|January 30, 2024
Summary
This study presents a minimal set of accessible phenotypic assays for antibiotic mode of action analysis. These methods help researchers distinguish between membrane and cell wall targets, even for complex antibiotics.
Area of Science:
- Microbiology and Molecular Biology
- Drug Discovery and Development
Background:
- Phenotypic analysis assays, such as bacterial cytological profiling (BCP), are crucial for antibiotic mode of action studies.
- Existing methods often require specialized equipment and expertise, hindering accessibility for non-expert researchers, especially for antibiotics with complex targets like the bacterial cell envelope.
- A need exists for simplified, affordable phenotypic assays that are easy to implement and interpret.
Purpose of the Study:
- To curate a minimal, accessible, and affordable set of phenotypic assays for distinguishing between bacterial membrane and cell wall targets.
- To identify assays capable of detecting dual-action inhibitors.
- To provide guidance for researchers with limited resources or specialized knowledge in bacterial cell biology.
Main Methods:
- Employed bacterial cytological profiling (BCP), membrane potential, fluidity, and cell wall synthesis assays.
- Utilized well-characterized reference antibiotics: valinomycin (potassium ionophore), vancomycin (Lipid II-binding glycopeptide), and nisin (dual-action lantibiotic).
- Assessed assay specificity and ease of interpretation.
Main Results:
- Identified a minimal set comprising BCP, a membrane-potentiometric probe, and fluorescent protein fusions to MinD and MreB.
- Recommended complementing this basic set with Laurdan-based fluidity measurements and a PliaI reporter fusion when necessary.
- Demonstrated the utility of these assays in distinguishing antibiotic targets and identifying dual-action compounds.
Conclusions:
- The curated minimal set of phenotypic assays is accessible, affordable, and effective for antibiotic mode of action analysis.
- These assays provide a practical solution for researchers lacking specialized equipment or extensive expertise in bacterial cell biology.
- The findings offer valuable guidance for broader implementation of phenotypic analysis in antibiotic research.
