The synthesis of (S)-β-macrocarpene from (2E,6E)-farnesyl diphosphate proceeds in two steps. The first step is the cyclization to (S)-β-bisabolene. The second step is the isomerization to (S)-β-macrocarpene (cf. EC 188.8.131.52, (S)-β-macrocarpene synthase). The enzyme requires Mg2+ or Mn2+ for activity.
Fujisawa, M., Harada, H., Kenmoku, H., Mizutani, S. and Misawa, N. Cloning and characterization of a novel gene that encodes (S)-β-bisabolene synthase from ginger, Zingiber officinale. Planta232 (2010) 121–130. [PMID: 20229191]