Cloning and sequence analysis of the Blumea balsamifera DC farnesyl diphosphate synthase gene.

Blumea balsamifera DC is a member of the Compositae family and is frequently used as traditional Chinese medicine. Blumea balsamifera is rich in monoterpenes, which possess a variety of pharmacological activities, such as antioxidant, anti-bacteria, and anti-viral activities. Farnesyl diphosphate synthase (FPS) is a key enzyme in the biosynthetic pathway of terpenes, playing an important regulatory role in plant growth, such as resistance and secondary metabolism. Based on the conserved oligo amino acid residues of published FPS genes from other higher plant species, a cDNA sequence, designated BbFPS, was isolated from B. balsamifera DC using polymerase chain reaction. The clones were an average of 1.6 kb and contained an open reading frame that predicted a polypeptide of 342 amino acids with 89.07% identity to FPS from other plants. The deduced amino acid sequence was dominated by hydrophobic regions and contained 2 highly conserved DDxxD motifs that are essential for proper functioning of FPS. Phylogenetic analysis indicated that FPS grouped with other composite families. Prediction of secondary structure and subcellular localization suggested that alpha helices made up 70% of the amino acids of the sequence.