Identification and characterization of three nearly identical linalool/nerolidol synthase from Acorus calamus. (October 2022) - Ibdah, Mwafaq
Abstract: Acorus calamus is a perennial aromatic medicinal plant from the Acorusaceae family, known for its pharmaceutical and medicinal value. A combined chemical, biochemical, and molecular study was conducted to evaluate the differential accumulation of volatile organic compounds (VOCs) in rhizomes and leaves of A. calamus essential oil . Here, we performed VOC profiling and transcriptome-based identification and functional characterization of terpene synthase (TPS) genes. A total of 110 VOCs were detected from the rhizomes and leaves of A. calamus, and some VOCs showed significant differences between them. The further transcriptome-based analysis led to the identification of six putative TPSs genes. In phylogenetic analysis, three TPSs belonged to the TPS-g clade, one to each of the TPS-a, TPS-c, and TPS-e clades. The heterologous E. coli-based expression of recombinant TPSs identified three genes ( AcTPS3, AcTPS4, and AcTPS5 ) as bifunctional linalool/nerolidol synthase. The correlation of TPS gene expression and VOC metabolite profiles supported the function of these genes in A. calamus. Our findings provide a roadmap for future efforts to enhance the molecular mechanisms of terpene biosynthesis and our understanding of Acorus-insect interactions. Graphical abstract: Image 1 Highlights: Acorus calamus essential oil showed insecticidal activity against carrot psylla. Six terpene synthases were identified from Acorus calamus. A. calamus AcTPS3, AcTPS4 and AcTPS5 showed bifunctional linalool/nerolidol synthase activity. Expression analysis suggests that the enzymes may play a role in terpene volatiles biosynthesis.