Probable sesquiterpene synthase. Binds 3 Mg(2+) ions per subunit. The Asp-Asp-Xaa-Xaa-Asp/Glu (DDXXD/E) motif is important for the catalytic activity, presumably through binding to Mg(2+). Does not produce any detectable product when tested in vitro. Belongs to the terpene synthase family.