Geranylgeranyl-Diphosphate Geranylgeranyltransferase

**Definition:** An enzyme that catalyzes the condensation of two molecules of geranylgeranyl diphosphate to give prephytoene diphosphate. The prephytoene diphosphate molecule is a precursor for CAROTENOIDS and other tetraterpenes.

**Tree numbers:** - D08.811.913.225.443

**Synonyms:** - Geranylgeranyl-Pyrophosphate Synthase - Phytoene Synthetase - Prephytoene-Diphosphate Synthase - Geranylgeranyl Pyrophosphate Synthase