2025/09/28 by Fabio Strati, Mariana P. Cali, Yehudi Bloch +6 · 1 voice · 3 citations
Biochemistry, Genetics and Molecular Biology · Immunology and Microbiology · #Amyloid (mycology) #Amyloid fibril #Antimicrobial #Antimicrobial Peptides and Activities #Antimicrobial peptides #Fibril #Lipid Membrane Structure and Behavior #Lipid bilayer fusion #Membrane #Nucleic acid #Peptide #RNA and protein synthesis mechanisms
paper · doi:10.1002/advs.202503997
published in Advanced Science 12(46), e03997 (Wiley)
openalex publication_date 2025/09/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Citropin 1.3 is an antimicrobial peptide secreted by the amphibian Litoria citropa (Southern bell frog). In this study, the structural and functional properties of its non-amidated form, which self-assembles into distinct fibrillar architectures, are investigated. Using cryogenic electron microscopy, X-ray crystallography, and fluorescence microscopy with model membranes and cells, diverse supramolecular structures, including canonical amyloid fibrils, multilayered nanotubes, and a novel mixed fibril type, are identified. In giant unilamellar vesicles, citropin 1.3 promoted membrane fusion and underwent lipid-induced phase separation. In mammalian cells, it permeabilized membranes, induced cell death, and colocalized with nucleic acids. These findings link antimicrobial activity to amyloid assembly and highlight the peptide's structural plasticity and potential biological functions, offering new insights into amyloid-based antimicrobial mechanisms.