Antimycin (ATM)

Antimycin A binds to the Qi site of cytochrome c reductase, thereby inhibiting the oxidation of ubiquinol in the electron transport chain of oxidative phosphorylation. The inhibition of this reaction disrupts the formation of the proton gradient across the inner membrane. The production of ATP is subsequently inhibited, as protons are unable to flow through the ATP synthase complex in the absence of a proton gradient. This inhibition also results in the formation of quantities of the toxic free radical superoxide.It has also been found to inhibit the cyclic electron flow within photosynthetic systems along the proposed ferredoxin quinone reductase pathway. Fungus-growing attine ants have been shown to use antimycins - produced by symbiotic Streptomyces bacteria - in their fungiculture, to inhibit non-cultivar. One research group studying these symbiotic Streptomyces bacteria recently identified the biosynthetic gene cluster for antimycins.