Borrelidin is a macrolide antibiotic initially produced by Streptomyces. Borrelidin exhibits anti-parasitic, antifungal, anticancer, and anti-angiogenic activities. This compound inhibits threonyl-tRNA synthetase/ligase, inhibiting growth and survival of Trypanosoma, Plasmodium, and Phytophthora. In acute lymphocytic leukemia (ALL) cells, borrelidin induces G1 phase cell cycle arrest, induces apoptosis, and inhibits proliferation. In endothelial cells, borrelidin inhibits formation of new capillary tubes and collapses pre-formed capillary tubes, inducing threonine- and caspase-dependent apoptosis.