Germacrene A synthase

In enzymology, a germacrene-A synthase (EC 4.2.3.23) is an enzyme that catalyzes the chemical reaction

2-trans,6-trans-farnesyl diphosphate ⇌ (+)-(R)-gemacrene A + diphosphate

Hence, this enzyme has one substrate, 2-trans,6-trans-farnesyl diphosphate, and two products, (+)-(R)-gemacrene A and diphosphate.

This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on phosphates. The systematic name of this enzyme class is 2-trans,6-trans-farnesyl-diphosphate diphosphate-lyase [(+)-(R)-germacrene-A-forming]. Other names in common use include germacrene A synthase, (+)-germacrene A synthase, (+)-(10R)-germacrene A synthase, GAS, 2-trans,6-trans-farnesyl-diphosphate diphosphate-lyase, and (germacrene-A-forming).