O-Methylsterigmatocystin is a natural product formed via methylation of sterigmatocystin. O-Methylsterigmatocystin is a xanthone metabolite isolated from several species of Aspergillus and Chaetomium. It is a precursor to aflatoxin G1 and B1 and, while it is considered mutagenic, teratogenic and carcinogenic, it is less potent than the aflatoxins. Research on this metabolite has focused on its genetic and phenotypic relationship to aflatoxins.
O-Methylsterigmatocystin is soluble in DMSO and DMF, moderately soluble in ethanol and methanol, and practically insoluble in water.
O-Methylsterigmatocystin is converted to aflatoxin B1(AFB1) via an oxidoreductase gene (ord1) in the last step of the aflatoxin biosynthetic pathway in A. flavux and A. parasiticus. The ord1 gene encodes a cytochrome P-450-type monooxygenase, and the gene has been assigned to a new P-450 gene family named CYP64. Results suggest that this gene is responsible for this complex and crucial step of the pathway that is unique to aflatoxigenic fungal species.
O-Methylsterigmatocystin can be used to study the aflatoxin biosynthetic pathway.
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