Carbonyl cyanide m-chlorophenyl hydrazone (CCCP; also known as [(3-chlorophenyl)hydrazono]malononitrile) is a chemical inhibitor of
oxidative phosphorylation. It is a
nitrile,
hydrazone and
protonophore. In general, CCCP causes the gradual destruction of living cells and death of the organism,[1][2] although mild doses inducing partial decoupling have been shown to increase median and maximum lifespan in C. elegans models, suggesting a degree of
hormesis.[3][4][5] CCCP causes an
uncoupling of the proton gradient that is established during the normal activity of electron carriers in the electron transport chain. The chemical acts essentially as an ionophore and reduces the ability of
ATP synthase to function optimally. It is routinely[6] used as an experimental uncoupling agent in cell and molecular biology, particularly in the study of
mitophagy,[7] where it was integral in discovering the role of the
Parkinson's disease-associated
ubiquitin ligaseParkin.[7] Outside of its effects on mitochondria, CCCP may also disrupt lysosomal degradation during autophagy.[7][8]