Biosynthetic Gene Cluster for Asperterpenols A and B and the Cyclization Mechanism of Asperterpenol A Synthase

Abstract

The biosynthetic gene cluster for the sesterterpenoids asperterpenols A and B from <i>Aspergillus calidoustus</i> CBS121601 is described. The cluster contains two genes, <i>acldAS</i> for a chimeric sesterterpene synthase and <i>acldA</i>-<i>P450</i> for a cytochrome P450 monooxygenase. The cyclization mechanism of the asperterpenol A synthase, catalyzing the formation of a unique sesterterpene with a 6/6/8/5 tetracyclic ring system, was studied using isotopically labeled terpene precursors.