Inhibiting Mrt4-rRNA interaction with fumaramidmycin-based derivatives as an antifungal strategy

The rise of drug resistance and limitations of current antifungal treatments highlight the urgent need for innovative antifungal strategies. Here we present the development of cis-fumaramidmycin-derived analogs inhibiting the interactions of ribosome assembly factor Mrt4 with rRNA to combat fungal infections. Through antifungal screening, we identified a promising lead 20 with strong efficacy against various drug-resistant fungi, including notorious super-fungus Candida auris. A comprehensive approach combining active-and-inactive-based protein profiling (AIBPP), chemical-genetic profiling, and fluorescence polarization revealed that the antifungal activity of 20 is primarily due to selectively inhibiting essential CaMrt4-rRNA interaction by conjointly covalent engaging C96&C189 on CaMrt4 but inactive for HuMrt4-rRNA interaction, thereby disrupting fungal ribosomal assembly. Therapeutic efficacy of 20 in both Galleria mellonella larvae and murine candidiasis models validate this antifungal strategy. Collectively, our studies provide a potential and much needed therapeutic strategy to address the rapidly rising burden of drug-resistant fungal infections.