Isolated from the aflatoxin-producing mold Aspergillus parasiticus [2]. Involved in aflatoxin biosynthesis. 5'-Oxoaverantin will spontaneously form averufin by intramolecular ketalisation. cf. EC 4.2.1.142, 5'-oxoaverantin cyclase.
Involvement of two cytosolic enzymes and a novel intermediate, 5'-oxoaverantin, in the pathway from 5'-hydroxyaverantin to averufin in aflatoxin biosynthesis.