Rapamycin

Rapamycin, also known as Sirolimus, is a macrolide compound produced by the bacterium Streptomyces hygroscopicus. It was initially discovered in a soil sample from Easter Island (Rapa Nui), hence its name.

Initially investigated for its potent antifungal properties, researchers later uncovered its more significant immunosuppressive and antiproliferative effects. Its mechanism of action is highly unique: it binds to the FK506-binding protein-12 (FKBP-12) inside cells, forming a complex that subsequently inhibits a crucial regulatory kinase called the "mechanistic Target of Rapamycin" (mTOR). mTOR plays a central role in cell growth, proliferation, metabolism, autophagy, and survival.