Visualization of the Assembly of a Two-Component Pore-Forming Toxin on a Target Membrane
Neval Yilmaz1,2, Anastasija Panevska3, Kristina Sepčić3
1Lipid Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
Nano Letters
|December 18, 2025
Summary
Pleurotus mushrooms create pore-forming toxins. Ostreolysin A6 (OlyA6) and pleurotolysin B (PlyB) interaction on membranes shows oligomerization and pore formation depend on OlyA6 density and molar ratio.
Area of Science:
- Biochemistry
- Molecular Biology
- Mycology
Background:
- Pleurotus mushrooms produce unique two-component pore-forming toxins.
- These toxins comprise a lipid-binding aegerolysin and a MACPF domain-containing protein (pleurotolysin B).
Purpose of the Study:
- Investigate the interaction between ostreolysin A6 (OlyA6) and pleurotolysin B (PlyB).
- Examine toxin behavior on ceramide phosphoethanolamine (CPE) and cholesterol (Chol) membranes.
- Determine the role of OlyA6 density and molar ratio in pore formation.
Main Methods:
- Studied OlyA6 and PlyB interaction on model membranes.
- Analyzed oligomerization and pore formation dynamics.
- Varied OlyA6 density and OlyA6/PlyB molar ratios.
Main Results:
- PlyB binding to OlyA6 induced oligomerization and pore formation.
- High OlyA6 density hindered oligomerization, forming arcs instead of rings.
- Crowding and unfavorable molar ratios impaired pore formation efficiency.
Conclusions:
- OlyA6 and PlyB association occurs on the membrane surface.
- Oligomerization and pore formation are regulated by OlyA6 density and OlyA6/PlyB molar ratio.
- Inefficient pore formation observed at high OlyA6/PlyB ratios validates findings.
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