Abstract
Aflatoxins are highly toxic and carcinogenic metabolites, which are produced by some strains of common fungi, mainly Aspergillus flavus and A. parasiticus. Aflatoxins B1, B2, G1 and G2 are the major aflatoxins produced by the fungi. Sterigmatocystin is a penultimate precursor of aflatoxins produced by many species including A. nidulans and also toxic and carcinogenic. Recently, the majority of enzyme reactions in aflatoxin/sterigmatocystin biosynthesis have been clarified, and the genes encoding the enzymes have been isolated. However, several unknown steps still remain. We have studied these unknown steps by using mainly enzymological methods. We finally clarified the detailed pathways of some of the unknown steps. We will summarize the newest information about the enzyme steps involved in aflatoxin/sterigmatocystin biosynthesis.
