In enzymology, a pinene synthase () is an enzyme that catalyzes the chemical reaction
geranyl diphosphate pinene + diphosphate
Hence, this enzyme has one substrate, geranyl diphosphate, and two products, pinene 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 geranyl-diphosphate diphosphate-lyase (cyclizing, pinene-forming). Other names in common use include beta-geraniolene synthase, (−)-(1S,5S)-pinene synthase, and geranyldiphosphate diphosphate lyase (pinene forming). This enzyme participates in monoterpenoid biosynthesis.
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