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Updated: Feb 14, 2026

A Colorimetric Assay of Citrate Synthase Activity in Drosophila Melanogaster
Published on: January 16, 2020
Characterization of santalene synthases using an inorganic pyrophosphatase coupled colorimetric assay
Gaoqun Hua1, Yiling Hu1, Chunyu Yang1
1Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, Collaborative Innovation Center of Chemical Science and Engineering, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, 300072, China.
Abstract:
We developed a colorimetric assay using yeast inorganic pyrophosphatase (IPP1) as a coupling enzyme to measure the activities of terpene synthases. IPP1 hydrolyzes pyrophosphate, the byproduct of terpene synthase catalyzed reactions, into orthophosphate, which can then be quantitated by reacting with molybdic acid to form a blue color compound. As a proof of concept, this method was used to quantitatively characterize three santalene synthases, SaSSy and SspiSSy involved in sandalwood oil biosynthesis, and a phylogenetically distant SanSyn from Clausena lansium. Our study provided the kinetic parameters of all three santalene synthases and demonstrated the validity of the enzyme couple colorimetric assay by the comparison of this assay with the existing GC-MS (Gas Chromatography-Mass Spectrometry) method.
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