Schullehner Katrin, Dick Regina, Vitzthum Florian, Schwab Wilfried, Brandt Wolfgang, Frey Monika, Gierl Alfons
Lehrstuhl für Genetik, Technische Universität München, Am Hochanger 8, 85350 Freising, Germany.
Phytochemistry. 2008 Nov;69(15):2668-77. doi: 10.1016/j.phytochem.2008.08.023. Epub 2008 Oct 15.
Benzoxazinoids are common defence compounds of the grasses and are sporadically found in single species of two unrelated orders of the dicots. In the three dicotyledonous species Aphelandra squarrosa, Consolida orientalis and Lamium galeobdolon the main benzoxazinoid aglucon is 2,4-dihydroxy-2H-1,4-benzoxazin-3(4H)-one (DIBOA). While benzoxazinoids in Aphelandra squarrosa are restricted to the root, in Consolida orientalis and Lamium galeobdolon DIBOA is found in all above ground organs of the adult plant in concentrations as high as in the seedling of maize. The initial biosynthetic steps in dicots and monocots seem to be identical. Indole is most probably the first specific intermediate that is oxygenated to indolin-2-one by a cytochrome P450 enzyme. C. orientalis has an active indole-3-glycerolphosphate lyase for indole formation that evolved independently from its orthologous function in maize. The properties and evolution of plant indole-3-glycerolphosphate lyases are discussed.
苯并恶嗪类化合物是禾本科植物常见的防御性化合物，在两个不相关的双子叶植物目单种植物中偶尔也能发现。在三种双子叶植物中，即单药花、东方菟葵和野芝麻，主要的苯并恶嗪类苷元是2,4 - 二羟基 - 2H - 1,4 - 苯并恶嗪 - 3(4H) - 酮（DIBOA）。单药花中的苯并恶嗪类化合物仅限于根部，而在东方菟葵和野芝麻中，成年植物地上所有器官都能发现DIBOA，其浓度与玉米幼苗中的浓度一样高。双子叶植物和单子叶植物最初生物合成步骤似乎相同。吲哚很可能是第一个被细胞色素P450酶氧化为吲哚 - 2 - 酮的特定中间体。东方菟葵有一种用于吲哚形成的活性吲哚 - 3 - 甘油磷酸裂解酶，它是从其在玉米中的直系同源功能独立进化而来的。本文讨论了植物吲哚 - 3 - 甘油磷酸裂解酶的特性和进化。
