Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Biochem Biophys Res Commun. 2013 Jun 21;436(1):73-8. doi: 10.1016/j.bbrc.2013.05.060. Epub 2013 May 23.
Eugenol, a volatile phenylpropene found in many plant species, exhibits antibacterial and acaricidal activities. This study attempted to modify the production of eugenol and its glycosides by introducing petunia coniferyl alcohol acetyltransferase (PhCFAT) and eugenol synthase (PhEGS) into hybrid aspen. Gas chromatography analyses revealed that wild-type hybrid aspen produced small amount of eugenol in leaves. The heterologous overexpression of PhCFAT alone resulted in up to 7-fold higher eugenol levels and up to 22-fold eugenol glycoside levels in leaves of transgenic aspen plants. The overexpression of PhEGS alone resulted in a subtle increase in either eugenol or eugenol glycosides, and the overexpression of both PhCFAT and PhEGS resulted in significant increases in the levels of both eugenol and eugenol glycosides which were nonetheless lower than the increases seen with overexpression of PhCFAT alone. On the other hand, overexpression of PhCFAT in transgenic Arabidopsis and tobacco did not cause any synthesis of eugenol. These results indicate that aspen leaves, but not Arabidopsis and tobacco leaves, have a partially active pathway to eugenol that is limited by the level of CFAT activity and thus the flux of this pathway can be increased by the introduction of a single heterologous gene.
丁香酚是一种存在于许多植物物种中的挥发性苯丙烯，具有抗菌和杀螨活性。本研究试图通过向杂种白杨中引入牻牛儿醇乙酰转移酶（PhCFAT）和丁香酚合酶（PhEGS）来改变丁香酚及其糖苷的产生。气相色谱分析显示，野生型杂种白杨叶片中产生少量丁香酚。单独过表达 PhCFAT 可使转基因白杨叶片中的丁香酚水平提高 7 倍，丁香酚糖苷水平提高 22 倍。单独过表达 PhEGS 仅导致丁香酚或丁香酚糖苷略有增加，而过表达 PhCFAT 和 PhEGS 可显著增加丁香酚和丁香酚糖苷的水平，但仍低于单独过表达 PhCFAT 时的增加水平。另一方面，在转基因拟南芥和烟草中过表达 PhCFAT 不会导致任何丁香酚的合成。这些结果表明，白杨叶片，而不是拟南芥和烟草叶片，具有部分活性途径生成丁香酚，该途径受到 CFAT 活性水平的限制，因此可以通过引入单个异源基因来增加该途径的通量。
