Target practice: The target of the antibiotic cyclomarin A was identified in Mycobacterium. Cyclomarin A (see structure) binds the regulatory subunit of the Clp protease complex with high affinity resulting in elevated proteolysis and cell death. The property of cyclomarin to kill both growing and nonreplicating mycobacteria makes the Clp protease a promising target for antitubercular drug discovery. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.