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06:17
A11-positive β-amyloid Oligomer Preparation and Assessment Using Dot Blotting Analysis
Published on: May 22, 2018
Structural Tuning of HEWL Amyloid Polymorphs Enhances Antibacterial Activity Against Gram-Positive and Gram-Negative
Biorxiv : the Preprint Server for Biology
|July 29, 2026
Summary
Structurally distinct amyloid polymorphs of hen egg white lysozyme (HEWL) show potent antibacterial activity against common bacterial strains. Flexible fibrils (FFs) offer strong antimicrobial effects with low cytotoxicity, making them promising for new antimicrobial materials.
Area of Science:
- Biophysics
- Materials Science
- Microbiology
Background:
- Amyloid fibrils are linked to diseases but also possess beneficial functions, such as antimicrobial defense.
- Hen egg white lysozyme (HEWL) can form distinct amyloid polymorphs with varying structures.
Purpose of the Study:
- To investigate the antibacterial activity of two HEWL amyloid polymorphs (flexible fibrils - FFs and rigid fibrils - RFs) compared to native HEWL.
- To assess the cytotoxicity of these amyloid structures against human neuroblastoma cells.
Main Methods:
- HEWL was converted into FFs and RFs.
- Fibril formation was confirmed using circular dichroism (CD) spectroscopy, thioflavin T (ThT) fluorescence, and transmission electron microscopy (TEM).
- Antibacterial activity was tested against *Staphylococcus aureus*, *Escherichia coli*, and *Salmonella Typhimurium*. Cytotoxicity was evaluated using SH-SY5Y cells.
Main Results:
- Both FF and RF polymorphs exhibited significantly enhanced antibacterial activity compared to native HEWL.
- FFs showed potent, concentration-dependent growth inhibition across all tested bacterial strains, achieving >90% inhibition at 600-800 μM.
- Cytotoxicity varied, with RFs showing higher toxicity than FFs and native HEWL.
Conclusions:
- Amyloid structure directly correlates with antibacterial efficacy and cytotoxicity.
- Flexible fibrils (FFs) of HEWL demonstrate potent antimicrobial activity with favorable cytotoxicity, identifying them as promising candidates for next-generation antimicrobial biomaterials.
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