Premium
Genomic and Targeted Approaches Unveil the Cell Membrane as a Major Target of the Antifungal Cytotoxin Amantelide A
Author(s) -
Elsadek Lobna A.,
Matthews James H.,
Nishimura Shinichi,
Nakatani Takahiro,
Ito Airi,
Gu Tongjun,
Luo Danmeng,
SalvadorReyes Lilibeth A.,
Paul Valerie J.,
Kakeya Hideaki,
Luesch Hendrik
Publication year - 2021
Publication title -
chembiochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 126
eISSN - 1439-7633
pISSN - 1439-4227
DOI - 10.1002/cbic.202000685
Subject(s) - ergosterol , yeast , biology , biochemistry , mechanism of action , saccharomyces cerevisiae , cell membrane , membrane , cytotoxicity , actin , mutant , microbiology and biotechnology , in vitro , chemistry , gene
Amantelide A, a polyhydroxylated macrolide isolated from a marine cyanobacterium, displays broad‐spectrum activity against mammalian cells, bacterial pathogens, and marine fungi. We conducted comprehensive mechanistic studies to identify the molecular targets and pathways affected by amantelide A. Our investigations relied on chemical structure similarities with compounds of known mechanisms, yeast knockout mutants, yeast chemogenomic profiling, and direct biochemical and biophysical methods. We established that amantelide A exerts its antifungal action by binding to ergosterol‐containing membranes followed by pore formation and cell death, a mechanism partially shared with polyene antifungals. Binding assays demonstrated that amantelide A also binds to membranes containing epicholesterol or mammalian cholesterol, thus suggesting that the cytotoxicity to mammalian cells might be due to its affinity to cholesterol‐containing membranes. However, membrane interactions were not completely dependent on sterols. Yeast chemogenomic profiling suggested additional direct or indirect effects on actin. Accordingly, we performed actin polymerization assays, which suggested that amantelide A also promotes actin polymerization in cell‐free systems. However, the C‐33 acetoxy derivative amantelide B showed a similar effect on actin dynamics in vitro but no significant activity against yeast. Overall, these studies suggest that the membrane effects are the most functionally relevant for amantelide A mechanism of action.