title: Characterization of α-humulene synthases responsible for the production of sesquiterpenes induced by methyl jasmonate in Aquilaria cell culture.
abstract: The resinous portions of Aquilaria and Gyrinops plants are known as 'agarwood' and have a distinctive fragrance. To examine the biosynthesis of these fragrant compounds, we previously established cell cultures of Aquilaria crassna in which the production of three sesquiterpenes (α-guaiene, α-humulene, and δ-guaiene) could be induced by methyl jasmonate (MJ), and showed that cloned δ-guaiene synthase from MJ-treated cells is involved in the synthesis of these three compounds, although only very small amounts of α-humulene are produced. In the present study, cDNAs encoding α-humulene synthases were also isolated. Three putative sesquiterpene synthase clones (AcHS1-3) isolated from the MJ-treated cells had very similar amino acid sequences and shared 52 % identity with δ-guaiene synthases. The recombinant enzymes catalyzed the formation of α-humulene as a major product. Expression of transcripts of the α-humulene synthase and δ-guaiene synthase genes in cultured cells increased after treatment with MJ. These results revealed that these α-humulene and δ-guaiene synthases are involved in the synthesis of three sesquiterpenes induced by MJ treatment.
authors.affiliation: Department of Pharmacognosy, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto, 606-8501, Japan.
authors.forename: Yukie
authors.initials: Y
authors.lastname: Kumeta
authors.affiliation: Department of Pharmacognosy, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto, 606-8501, Japan. michihoi@pharm.kyoto-u.ac.jp.
authors.forename: Michiho
authors.initials: M
authors.lastname: Ito
mesh_terms: D000085:Acetates / Q000737:chemistry*; D018929:Cell Culture Techniques; D003517:Cyclopentanes / Q000737:chemistry*; D000081222:Monocyclic Sesquiterpenes; D054883:Oxylipins / Q000737:chemistry*; D012717:Sesquiterpenes / Q000737:chemistry*; D029645:Thymelaeaceae / Q000737:chemistry*
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D000081222:Monocyclic Sesquiterpenes; D054883:Oxylipins; D012717:Sesquiterpenes; C042686:humulene; C072239:methyl jasmonate
keywords: Aquilaria crassna; Cell cultures; Functional characterization; Methyl jasmonate treatment; Terpene; α-humulene synthase