4.2.3.136 (2E,6E)-farnesyl diphosphate MrTPS2 shows a broader sesquiterpene product spectrum with the angular triquinane, alpha-isocomene, being the main compound. The enzyme produces detectable amounts of three other triquinanes, beta-isocomene, silphinene and modeph-2-ene. Like MrTPS1 it also produces (E)-beta-caryophyllene and alpha-humulene, but in low amounts Matricaria chamomilla var. recutita alpha-isocomene + diphosphate - ? 419643 4.2.3.136 (2E,6E)-farnesyl diphosphate reaction mechanism most likely involves repeated cycles of protonation/deprotonation of a neutral (-)-(E)-beta-caryophyllene intermediate. The deprotonation of the final isocomyl carbocation can occur either at C1 or C13, resulting in the main product alpha-isocomene and the minor product beta-isocomene Matricaria chamomilla (-)-alpha-isocomene + diphosphate - ? 429472