Mycotoxins - Their Biosynthesis in Alternaria

Alternaria produce a wide assortment of toxic and nontoxic secondary metabolites. A brief summary of the numerous secondary metabolites of Alternaria and their toxicity is followed by a presentation of the current view of the polyketide biosynthetic mechanism and its application to the biosynthesis of these compounds. Possible mechanisms for the biosynthesis of alternariol, alternariol methyl ether, and other dibenzo-α-pyrones are presented, as well as mechanisms for the biosynthesis of tenuazonic acid and altertoxin I. Bioregulation of the production of these materials by light, heat, nutrients and NADPH production, and the role of mannitol in NADPH formation are also discussed.