A collaborative research team has uncovered a previously unknown mechanism of action of yaku'amide B, a structurally complex peptidic natural product derived from deep-sea sponge found in the waters near Yakushima Island, Japan. Natural products often exhibit multifaceted biological activities due to their structural complexity, interacting transiently with multiple biomolecules. Yaku'amide B was previously shown to inhibit ATP synthase, an essential enzyme for cellular energy production. However, this alone could not fully explain its unique anticancer properties.