A cDNA(af1) encoding farnesyl pyrophosphate synthase AaFPS1 (FPS, EC2.5.1.1/EC2.5.1.10) from a high yield Artemisia annua strain 025 has been cloned from its cDNA library. Sequence analysis showed that the cDNA en-coded a protein of 343 amino acid (aa) residues with mo-lecular weight of 39 kD. Deduced aa sequence of the cDNA was similar to FPS from other plants, yeast and mammals, containing 5 conserved domains found in both prenyl trans-ferase and polyprenyl synthase. The expression of the cDNA in Escherichia coli showed measurable specific activity of FPS in vitro. The enzyme was purified by ion exchange chromatography and its kinetics was measured. These re-sults would further promote the molecular regulation of ar-temisinin biosynthesis.
