University of Pennsylvania scientists discovered novel ribosomally synthesized and post-translationally modified peptides (RiPPs) from Aspergillus flavus with potent activity against leukemia cells. These asperigimycins feature complex heptacyclic structures and were identified through genetic knockouts and metabolic profiling, marking a breakthrough in fungal natural product research. This work opens avenues for developing fungal RiPPs as anticancer agents, expanding the repertoire beyond traditional bacterial-derived peptides.