ID 4.2.3.203 DE isoelisabethatriene synthase. CA (2E,6E,10E)-geranylgeranyl diphosphate = diphosphate + CA isoelisabethatriene. CC -!- Isolated from the bacterium Streptomyces clavuligerus. CC -!- The 1-proR hydrogen atom of geranylgeranyl diphosphate is involved in CC a 1,3-hydride shift to the side-chain. CC -!- The enzyme also produces hydropyrene, hydropyrenol, and traces of CC other diterpenoids. cf. EC 4.2.3.201 and EC 4.2.3.202. //