Poster: Metabolic Engineering

Abs # 999: Metabolic engineering of monoterpene biosynthesis with Perilla limonene synthase in tobacco

Presenter:	Yazaki, Kazufumi , yazaki@kuwri.kyoto-u.ac.jp
Authors	Yazaki, Kazufumi  (A) (B)  Ohara, Kazuaki  (B)   Ujihara, Tomomi  (B)   Sato, Fumihiko  (B)
Affiliations:	(A): Wood Research Institute, Kyoto University (B): Graduate School of Biostudies, Kyoto University
Web Site:	http://133.3.24.201:8931/LGE/

Limonene, a monocyclic monoterpene, exhibits chemotherapeutic and chemopreventive potential in breast cancer patients. Limonene is biosynthesized by a monoterpene synthase, i. e. limonene synthase (LS) via the stereo-specific cyclization of geranyl diphosphate (GPP). In an attempt to engineer monoterpene biosynthesis, we introduced three expression constructs of LS cDNA of Perilla frutescens into tobacco, which were designed to be localized in either plastid, cytosol or endoplasmic reticulum (ER), to examine differences in enzyme activity and the productivity of limonene. High and moderate enzyme activity, respectively, was observed for plastid- and cytosol-localized LS, whereas no enzyme activity was seen for ER-localized LS, suggesting that plastid or cytosol is the preferable compartment for LS. The formation of limonene in vivo was confirmed by gas chromatography-mass spectrometry (GC-MS) in both leaf extract and the headspace of plastid- and cytosol-localized LS transgenic plants. The possibility of genetic engineering of monoterpene production is discussed.