Abstract
Cyclopiazonic acid (CPA) is an indole-tetramic acid mycotoxin produced by some strains of Aspergillus flavus. Characterization of the CPA biosynthesis gene cluster confirmed that formation of CPA is via a three-enzyme pathway. This review examines the structure and organization of the CPA genes, elucidates the specific roles of functional domains of each enzyme in carrying out catalytic conversions leading to CPA production, and delineates the molecular basis for the lack of CPA production by A. flavus strains currently being used in biocontrol of aflatoxin contamination of crops.