Multidomain P450 Epoxidase and a Terpene Cyclase from the Ascochlorin Biosynthetic Pathway in Fusarium sp.

Ascochlorin is a medicinally important fungal meroterpenoid. Its biosynthetic pathway in Fusarium sp. was identified, and the stereoselective epoxidation of the farnesyl group by the multidomain, soluble P450 monooxygenase AscE and the subsequent formation of the unique timethylcyclohexanone ring by the membrane-bound cyclase AscF were investigated. Precursor-directed biosynthesis generated novel bromo-substituted derivatives, which exhibited potent cytotoxic activities. This study paves the way for the future metabolic engineering of medicinally important meroterpenoids for drug discovery.