Studies on the Properties and Bio-Functions of Prenyl Epoxidase

异戊二烯环氧酶的性质及生物功能研究

• 批准号: 09660109
• 负责人: TAHARA Satoshi
• 金额: $ 2.11万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09660109/
• 关键词: Botrytis cinerea; prenyl epoxidase; monooxygenase; detoxification; phytopatogen resistance; FAD-dependent monooxygenase; isoflavonoids; prenylated flavonoids; プレニルフラボノイド; エポキシダーゼ; ファイトアレキシン; イソフラボン; FAD依存オキシゲナーゼ

Crude protein extracts from Botrytis cinerea preincubated with 6-prenylnaringenin (6-PN) for 20 hr catalyzed the prenyl epoxidation of 7-O-methyl-luteone, The resulting epoxide was non-enzymatically and slowly converted into the corresponding dihydrofurano derivative in a buffer solution at pH 7.5. Preparation of cell-free extracts in the presence of 6-PN from the mycelia without preincubation with 6-PN hardly showed the epoxidizing activity. These facts revealed that the substrate analogue 6-PN took a role not as an enzyme stabilizer, but as an enzyme inducer. The enzyme reaction depends on diatomic oxygen and NADPH.Low amounts of FAD are necessary for maximal enzyme activity. Because the enzymatic activity was not inhibited by several inhibitors of cytochrome P-450 in addition to carbon monooxide and cytochrome c, this enzyme seems to belong not to the monooxygenase group dependent on cytochrome P-450, but to that dependent on FAD.Although about half of the total enzyme activity was found in the 125,000 g supernatant, the specific activity for the epoxidation reaction of 125,000 g pellets was higher (x 3.7) than that of the soluble fraction. Substrate specificity was also examined using someprenylisoflavones differing in position and number of prenyl substitution. Some properties of the present prenylflavonoid epoxidase dependent on FAD was discussed in comparison with otherflavoprotein monooxygenases and prenyl cyclization enzymes concerning phytoalexin biosynthesis.In addition to these research results, a review article "Fungal metabolism of flavonoids and related phytoalexins" was described to discuss the biological aspects of prenylated flavonoid metabolisms in microorganisms and plants.

灰葡萄孢菌（Botrytis cinerea）的粗蛋白提取物与6-异戊烯基柚皮素（6-PN）共孵育20小时后，催化异戊烯基环氧化7-O-甲基-叶黄素，得到的环氧化物在pH 7.5的缓冲溶液中非酶促缓慢转化为相应的二氢呋喃衍生物。在6-PN存在下，从菌丝体制备无细胞提取物而不与6-PN预孵育几乎没有显示环氧化活性。这些事实表明，底物类似物6-PN的作用不是作为酶的稳定剂，但作为酶的诱导剂。酶的反应依赖于双原子氧和NADPH。低量的FAD是最大酶活性所必需的。由于酶活性不受除一氧化碳和细胞色素c之外的几种细胞色素P-450抑制剂的抑制，因此该酶似乎不属于依赖于细胞色素P-450的单加氧酶基团，而是属于依赖于FAD的单加氧酶基团。000 g颗粒的含量高于可溶性级分的含量（× 3.7）。底物特异性也进行了检查，使用不同的位置和数目的异戊烯基取代someprenylisoflavones。本文讨论了异戊烯基类黄酮环氧酶的一些特性，并与其它的黄素蛋白单加氧酶和异戊烯基环化酶进行了比较，讨论了异戊烯基类黄酮环氧酶在植物抗毒素生物合成中的作用，并在“Fungal metabolism of flavonoids and related phytoalexins”一文中对异戊烯基类黄酮代谢在微生物和植物中的生物学意义进行了讨论。

项目成果

Yasufumi Katagiri: "Farulic Acid Esters of Unsaturated Higher Alcohols from Lupinus luteus Roots" Phytochemistry. 46(2). 347-352 (1997)

Yasufumi Katagiri：“来自羽扇豆根的不饱和高级醇的法鲁酸酯”植物化学。

Mariko Shibatani: "A Major Fungitoxin of Pachira aquatica and its Topical Accumulation in the Outer Bark" Journal of Chemical Ecology. 25(2). 347-353 (1999)

Mariko Shibatani：“发财树的一种主要真菌毒素及其在外树皮中的局部积累”化学生态学杂志。

Satoshi Tahara: "Simple Flavonoids Possessing Complex Biological Activity in"Studies in Natural Products Chemistry"Ed by Atta-urRahman" Elsevier, Netherlands(in press), 校正時54ページ (1999)

Satoshi Tahara：“Studies in Natural Products Chemistry”Ed by Atta-urRahman 中的“Simple Flavonoids Possessing Complex Biological Activity”，爱思唯尔，荷兰（正在印刷中），校对时 54 页（1999 年）

Weiguang Ma.: "Isoflavonoid Glycosides from Eriosema tuberosum" Phytochemistry. 49(1). 251-254 (1998)

马伟光：“马铃薯异黄酮苷”植物化学。

Jun Ushiki: "Suppressive Effect of Geranium pratense L.on Common Scab of Potato and Identification of the Active Compound" Soil Science and Plant Nutrition. 44(2). 157-165 (1998)

Jun Ushiki：“天竺葵对马铃薯疮痂病的抑制作用及活性化合物的鉴定”土壤科学与植物营养。