Structural Diversification of Andiconin-Derived Natural Products by α-Ketoglutarate-Dependent Dioxygenases.

The biosynthetic gene cluster of the fungal meroterpenoid emeridone F (8) was discovered in the genome of Aspergillus sp. TJ23, and its late-stage biosynthesis was elucidated by characterizing two α-ketoglutarate (αKG)-dependent dioxygenases, SptF and SptN. SptF catalyzes oxidative rearrangement followed by epoxidation, whereas SptN serves as the C-9 hydroxylase. Our study provides insight into the biosynthetic mechanisms of other andiconin (1)-derived natural products, exemplifying the important roles of αKG-dependent enzymes in the structural complexifications.