apo-Enopeptin methyl ester is the ring-opened derivative of enopeptin. The activity of apo-enopeptin methyl ester is little known, however its parent, enopeptin A, is active against bacteriophage has potent antibacterial activity against Gram positive and Gram negative bacteria, including MRSA. Enopeptin A is the most non-polar of the acyldepsipeptide (ADEP) antibiotics which include the recently rediscovered compounds, A54556 A and B, that act by activating and disregulating Clp-family proteins.