Eilon Barnea

eLife Assessment This study presents valuable findings on the differential effects of RNA on the phase separation, aggregation dynamics, and bioactivity of PSMα3 and LL-37. The authors provide solid evidence from complementary biophysical and cell-based experiments that RNA influences peptide assembly and associated in vitro activities. The study is of interest for understanding interactions between amyloidogenic peptides and nucleic acids.

Abstract Amyloids, classically associated with neurodegenerative disease, also play important roles in infection and immunity. Phenol-soluble modulins (PSMs) from Staphylococcus aureus are amyloid-forming virulence peptides that contribute to cytotoxicity, immune modulation, and biofilm stability. PSMα3 forms cross–α amyloid fibrils and shares sequence and α-helical self-assembly features with LL-37, a human host-defence peptide that forms non-amyloid α-helical assemblies.

Abstract FapC and FapB are biofilm-associated amyloids involved in the virulence of Pseudomonas and other bacteria. We herein demonstrate their exceptional thermal and chemical resilience, suggesting that biofilm structures might withstand standard sterilization, thereby contributing to the persistence of P. aeruginosa infections.