The invention relates to a multifunctional germacrene-D synthase and a
polynucleotide encoding it. Included also are genetic constructs,
transgenic organisms, plant selection methods and biofermentation
methods. The enzyme may be used to prepare germacrene-D and/or other
sesquiterpenes such as germacrene-D, delta-cadinene, gamma-cadinene,
gamma-muurolene, gamma-elemene, delta-elemene, elemol or germacrene-B.