Heterologous expression of four clade-A bifunctional terpene synthases (BFTSs), giving di/sesterterpenes with unique polycyclic carbon skeletons such as sesterfisherol, enabled the isolation of the sesterterpenes Bm1, Bm2, Bm3, and Pb1. Their structures suggested that formation of the products occurs via various diastereomeric carbocation intermediates, allowing the proposal that clade-A BFTSs catalyze three-step cyclizations using several stereofacial combinations of allylic cation-olefin pairs in the corresponding intermediates to generate various stereoisomers.

Indole sesquiterpene sespendole, which has been isolated from the filamentous fungus Pseudobotrytis terrestris FKA-25, is a specific inhibitor of lipid droplet synthesis in mouse macrophages. The biosynthetic pathway that involves genes encoding six enzymes (spdEMBQHJ) was elucidated through heterologous expression of spd genes in Aspergillus oryzae, biotransformation experiments, and in vitro enzymatic reactions with a recombinant protein, thereby revealing the mechanism underlying the characteristic modification on the indole ring, catalyzed by a set of prenyltransferase (SpdE)/cytochrome P450 (SpdJ) enzymes. Functional analysis of the homologous genes encoding these enzymes involved in the biosynthesis of lolitrem allowed a biosynthetic pathway for the bicyclic ring skeleton fused to the indole ring to be proposed.