Baba Mariko, Yamada Ken-Ichi, Ito Michiho
Department of Pharmacognosy, Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo, Kyoto 606-8501, Japan.
Department of Pharmaceutical Organic Chemistry, Graduate School of Pharmaceutical Sciences, Tokushima University, Shomachi, Tokushima 770-8505, Japan.
Plants (Basel). 2020 May 1;9(5):577. doi: 10.3390/plants9050577.
Phenylpropanoid volatile components in plants are useful and valuable not only as flavorings, but also as medicines and food supplements. The pharmacological actions and toxicities of these compounds have been well studied but their synthetic pathways are generally unclear. In this study, we mined expressed sequence tag libraries of pure strains of perilla maintained for over 30 years for their oil type and conducted gas chromatography-mass spectrometry analyses of the perilla oils to confirm the presence of monohydrates speculated to be intermediates of the phenylpropene synthetics pathways. These putative monohydrate intermediates and their regioisomers were synthesized to identify the reaction products of assays of heterologously expressed enzymes. An enzyme involved in the synthesis of a phenylpropanoid volatile component was identified in perilla. Expression of this enzyme in showed that it is a member of the cytochrome P450 family and catalyzes the introduction of a hydroxy group onto myristicin to form an intermediate of dillapiole. The enzyme had high sequence similarity to a CYP71D family enzyme, high regiospecificity, and low substrate specificity. This study may aid the elucidation of generally unexploited biosynthetic pathways of phenylpropanoid volatile components.
植物中的苯丙烷类挥发性成分不仅作为调味剂有用且有价值，还可作为药物和食品补充剂。这些化合物的药理作用和毒性已得到充分研究，但其合成途径通常尚不清楚。在本研究中，我们挖掘了保存超过30年的紫苏纯系的表达序列标签文库以获取其油型，并对紫苏油进行气相色谱 - 质谱分析，以确认推测为苯丙烯合成途径中间体的一水合物的存在。合成了这些假定的一水合物中间体及其区域异构体，以鉴定异源表达酶测定的反应产物。在紫苏中鉴定出一种参与苯丙烷类挥发性成分合成的酶。该酶在[此处原文缺失相关信息]中的表达表明它是细胞色素P450家族的成员，并催化在肉豆蔻醚上引入羟基以形成莳萝脑的中间体。该酶与CYP71D家族酶具有高度序列相似性、高区域特异性和低底物特异性。本研究可能有助于阐明苯丙烷类挥发性成分通常未被开发的生物合成途径。
