The Purification and Properties of Geranylgeranyl Pyrophosphate Synthetase from Pumpkin Fruit*

Separation of geranylgeranyl pyrophosphate synthetase and farnesyl pyrophosphate synthetase [EC 2. 5. 1. 1] was achieved by DEAE-Sephadex chromatography of pumpkin fruit extracts. The purified preparation of geranylgeranyl pyrophosphate synthetase was able to catalyze not only the condensation of isopentenyl pyrophosphate with farnesyl pyrophosphate but also the condensation of isopentenyl pyrophosphate with dimethylallyl or geranyl pyrophosphate, so that it catalyzed the consecutive chain elongation of C5↑C10↑C15↑C20 without accumulation of any intermediate. Mn2+ was an absolute requirement, and Mg2+ was much less effective.