Kwon Moonhyuk, Cochrane Stephen A, Vederas John C, Ro Dae-Kyun
Department of Biological Sciences, University of Calgary, 2500 University Dr. NW, Calgary T2N 1N4, Canada; Department of Agricultural Biotechnology and Research Institute of Agricultural Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Canada.
FEBS Lett. 2014 Dec 20;588(24):4597-603. doi: 10.1016/j.febslet.2014.10.031. Epub 2014 Nov 4.
Drimenol, a sesquiterpene alcohol, and its derivatives display diverse bio-activities in nature. However, a drimenol synthase gene has yet to be identified. We identified a new sesquiterpene synthase cDNA (VoTPS3) in valerian plant (Valeriana officinalis). Purification and NMR analyses of the VoTPS3-produced terpene, and characterization of the VoTPS3 enzyme confirmed that VoTPS3 synthesizes (-)-drimenol. In feeding assays, possible reaction intermediates, farnesol and drimenyl diphosphate, could not be converted to drimenol, suggesting that the intermediate remains tightly bound to VoTPS3 during catalysis. A mechanistic consideration of (-)-drimenol synthesis suggests that drimenol synthase is likely to use a protonation-initiated cyclization, which is rare for sesquiterpene synthases. VoTPS3 can be used to produce (-)-drimenol, from which useful drimane-type terpenes can be synthesized.
蛇床子醇，一种倍半萜醇，及其衍生物在自然界中表现出多种生物活性。然而，蛇床子醇合酶基因尚未被鉴定出来。我们在缬草属植物（缬草）中鉴定出一种新的倍半萜合酶cDNA（VoTPS3）。对VoTPS3产生的萜类化合物进行纯化和核磁共振分析，并对VoTPS3酶进行表征，证实VoTPS3合成（-）-蛇床子醇。在饲喂试验中，可能的反应中间体法呢醇和蛇床子二磷酸不能转化为蛇床子醇，这表明中间体在催化过程中与VoTPS3紧密结合。对（-）-蛇床子醇合成的机理研究表明，蛇床子醇合酶可能使用质子化引发的环化反应，这在倍半萜合酶中很少见。VoTPS3可用于生产（-）-蛇床子醇，由此可合成有用的卓酚酮型萜类化合物。
