Cyclopiazonic acid


Cyclopiazonic acid is a toxic fungal secondary metabolite. Chemically, CPA is related to ergoline alkaloids. CPA was originally isolated from Penicillium cyclopium and subsequently from other fungi including Penicillium griseofulvum, Penicillium camemberti, Penicillium commune, Aspergillus flavus, and Aspergillus versicolor. CPA only appears to be toxic in high concentrations. Ingestion of CPA causes one to be an anorexic, to be dehydrated, to lose weight, to be immobile, and has some sign of spasm when near death. They can be found in molds, corns, peanuts, and other fermented products, such as cheese and sausages. Biologically, CPA is a specific inhibitor of SERCA ATPase in intracellular Ca2+ storage sites. CPA inhibits SERCA ATPase by keeping it in one specific confirmation, thus, preventing it from forming another. CPA also binds to SERCA ATPase at the same site as another inhibitor, thapsigargin. In this way, CPA lowers the ability of SERCA ATPase to bind an ATP molecule.