[22] Geranylpyrophosphate Synthetase-Geranylgeranylpyrophosphate Synthetase from Micrococcus Luteus

This chapter describes the preparation of the geranylpyrophosphate synthetase-geranylgeranylpyrophosphate synthetase from Micrococcus luteus. Geranylgeranylpyrophosphate synthetase that catalyzes the three sequential reactions C5 → C10 → C15→ C20 is also found in M. luteus as well as in higher plants. This chapter discusses the geranylgeranylpyrophosphate synthetase, which lacks geranyl-transferring activity. A partially purified geranylpyrophosphate synthetase preparation obtained from Micrococcus luteus catalyzes the synthesis of geranyl pyrophosphate from dimethylallyl pyrophosphate and isopentenyl pyrophosphate and of all-trans-geranylgeranyl pyrophosphate from farnesyl pyrophosphate and isopentenyl pyrophosphate, but it does not catalyze the synthesis of farnesyl pyrophosphate from geranyl pyrophosphate and isopentenyl pyrophosphate. The principle of the assay method is described in the chapter. Purification of enzyme is described in the chapter. In purification, there are several steps are discusses in the chapter—namely, extraction, fractionation, and chromatography.