- 醗酵工学会誌 : hakkokogaku kaishi
- vol.61, no.3, 1983
Patulin is a typical mycotoxin originally isolated from Penicillium patulum as an antibiotic, and the patulin biosynthetic pathway is a classical example of the large group of polyacetate-dervied secondary metabolites known as polyketides. Unexpected metabolites produced by a patulin-deficient mutant revealed a new portion of the pathway. We have investigated the patulin biosynthetic pathway with the aid of several patulin-deficient mutants, pathway enzymology, bioconvesion of metabolites, and immobilized cell techniques. It was found that three mycotoxins (phyllostine, isoepoxydon and ascladiol) and a new lactone (neopatulin) exist on the pathway. Two dehydrogenases among the pathyway enzymes were characterized. Furthemore, in contrast to the accepted assumption, monooxygenase mediated the ring cleavage of an aromatic precursor, gentisaldehyde. Finally, the patulin pathway becomes twice as long as the portion known before 1978,and is one of the best characterized pathways of secondary metabolism. In this monograph, mechanisms of the conversion of phyllostine to neopatulin, and neopatulin to phyllostine, are proposed, and a pathway for the related mycotoxin, penicillic acid, is also discussed.