Casbene synthase

In enzymology, a casbene synthase (EC 4.2.3.8) is an enzyme that catalyzes the chemical reaction

Hence, this enzyme has one substrate, geranylgeranyl diphosphate, and two products, casbene 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 geranylgeranyl-diphosphate diphosphate-lyase (cyclizing, casbene-forming). Other names in common use include casbene synthetase, and geranylgeranyl-diphosphate diphosphate-lyase (cyclizing). This enzyme participates in diterpenoid biosynthesis.