Bifunctional terpene synthase; part of the gene cluster that mediates the biosynthesis of sesterfisheric acid (PubMed:26332841). The bifunctional terpene synthase NfSS converts DMAPP and IPP, and also GGPP, into sesterfisherol (PubMed:26332841, PubMed:29410538). The C-terminal prenyltransferase (PT) domain of NfSS catalyzes formation of GFPP, whereas the N-terminal terpene cyclase (TC) domain catalyzes the cyclization of GFPP to sesterfisherol (PubMed:26332841, PubMed:29410538). The cyotochrome P450 monooxygenase NfP450 then catalyzes oxidative modifications of sesterfisherol into sesterfisheric acid (PubMed:26332841). (2E,6E)-farnesyl diphosphate + isopentenyl diphosphate = (2E,6E,10E)-geranylgeranyl diphosphate + diphosphate (2E,6E,10E)-geranylgeranyl diphosphate + isopentenyl diphosphate = (2E,6E,10E,14E)-geranylfarnesyl diphosphate + diphosphate (2E,6E,10E,14E)-geranylfarnesyl diphosphate + H2O = diphosphate + sesterfisherol Secondary metabolite biosynthesis; terpenoid biosynthesis. Hexamer. The conserved DDXXD motifs as well as the NSE/DTE motif are important for the catalytic activity, presumably through binding to Mg(2+). In the N-terminal section; belongs to the terpene synthase family. In the C-terminal section; belongs to the FPP/GGPP synthase family.