Coniontins, lipopetaibiotics active against Candida auris identified from a microbial natural product fractionation library

The rise of drug-resistant fungal pathogens, including Candida auris, highlights the urgent need for innovative antifungal therapies. We have developed a cost-effective platform combining microbial extract prefractionation with rapid mass spectrometry-bioinformatics-based dereplication to efficiently prioritize previously uncharacterized antifungal scaffolds. Screening C. auris and Candida albicans reveals coniotins, lipopeptaibiotics isolated from Coniochaeta hoffmannii, which are undetectable in crude extracts. Coniotins exhibits potent activity against critical priority fungal pathogens listed by the World Health Organization, including C. albicans, Cryptococcus neoformans, multidrug-resistant Candida auris, and Aspergillus fumigatus, with high selectivity and low resistance potential. Coniotin A targets beta-glucan, compromising fungal cell wall integrity, remodelling, and sensitizing C. auris to caspofungin. Identification of its hybrid polyketide synthase–nonribosomal peptide synthetase biosynthetic gene cluster facilitates discovering structurally diverse lipopeptaibiotics. Here, we show that natural product prefractionation enables the discovery of previously hidden bioactive scaffolds and introduces coniotins as candidates for combating multidrug-resistant fungal pathogens. In this work, authors utilise a prefractionation natural product extract screening platform, which uncovers coniotins, lipopeptaibiotics with broad antifungal activity and a mechanism of action that targets fungal cell wall β-glucan.