C3 unit addition reaction accompanied by formation of C-C bond in phytotoxin biosynthesis of phytopathogen.

植物病原体的植物毒素生物合成中伴随C-C键形成的C3单元加成反应。

• 批准号: 11660111
• 负责人: NAKAJIMA Hiromitsu
• 金额: $ 2.05万
• 依托单位: Tottori University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11660111/
• 关键词: plant pathogens; phytotoxins; biosynthesis; Bipolaris sorokiniana; sesquiterpene; ^<14>C labeled compound; ^3H labeled compound; GCMS; ^<18>O標識化合物

Sorokinianin is a phytotoxin produced by a strain (OB-25-1) of Bipolaris sorokiniana, a pathogen causing spot blotch or foot and root rot diseases of wheat and other grasses. This toxin is assumed to be composed of a helminthosporol-type sesquiterpene and a C_3 portion. The feeding experiments conducted previously suggested that sorokinianin was synthesized from prehelminthosporol by reactions that include the addition of a member of the TCA cycle, decarboxylation and lactonization. A feeding experiment with L-[hydroxy-^<18>O] malic acid indicated that the direct C_3 unit precursor was not malic acid/oxalacetic acid but fumaric acid/succinic acid. The aim of this research is to identify the product formed just after addition of fumaric acid/succinic acid to prehelminthosporol. For this purpose we prepared ^<14>C labeled prehelminthosporol (1.7 mg, specific radioactivity 35 KBq/mg) from B.sorokiniana cultured on the medium containing ^<14>C labeled glucose. Among the fractions obtained from the mycelium incubated with both ^<14>C labeled prehelminthosporol and ^3H labeled succinic acid we found a fraction which had both ^<14>C and ^3H radioactivity. Then we analyzed the same fraction obtained in the cold run as in the radio isotopic experiment by GCMS after acetylation and methylation.

Sorokinianin是由一株（OB-25-1） sorokiniana产生的一种植物毒素，是一种引起小麦和其他禾草的斑疹病或足腐病和根腐病的病原体。这种毒素被认为是由线虫孢醇型倍半萜和C_3部分组成的。先前进行的饲养实验表明，由前helminthosporol通过添加TCA循环成员，脱羧和内酯化反应合成了sorokinianin。L-[羟基-^<18>]苹果酸投喂试验表明，直接C_3单元前体不是苹果酸/草酸，而是富马酸/琥珀酸。本研究的目的是鉴定富马酸/琥珀酸加入前孢菌素后形成的产物。为此，我们从含有^<14>C标记的葡萄糖培养基上培养的sorokiniana中制备了^<14>C标记的前叶孢素（1.7 mg，比放射性35 KBq/mg）。在用^<14>C标记的前孢菌素和^3H标记的琥珀酸孵育得到的菌丝体中，我们发现了一个同时具有^<14>C和^3H放射性的部分。然后我们分析了经乙酰化和甲基化后，在冷运行中得到的与放射性同位素实验中相同的组分。

项目成果

F.Furumoto: "Biosynthesis of phytotoxin neovasinin and its related metabolites, neovasipyrones A and B and neovasifuranones A and B, in the phytopathogenic fungus Neocosmospora vasinfecta"J.Chem.Soc.,Perkin Trans.1. 1999. 131-135 (1999)

F.Furumoto：“在植物病原真菌 Neocosmospora vasinfecta 中植物毒素 neovasinin 及其相关代谢物、neovasipyrones A 和 B 以及 neovasifuranones A 和 B 的生物合成”J.Chem.Soc.，Perkin Trans.1。

Y.Fujii,H.Tani,M.Ichinoe and H.Nakajima: "Zygosporin D and two new cytochalasins produced by the fungus Metarrhizium anisopliae"Journal of Natural Products. 63. 132-135 (2000)

Y.Fujii、H.Tani、M.Ichinoe 和 H.Nakajima：“由真菌绿僵菌产生的接合孢菌素 D 和两种新的细胞松弛素”天然产物杂志。

P.Singh,P.Park,R.Bugiani,P.Cavanni,H.Nakajima et.al.: "Effects of host-selective SV-toxin from Stemphylium vesicarium, the cause of brown spot of European pear plants, on ultrastructure of leaf cells"J. Phytopathology. 148. 87-93 (2000)

P.Singh、P.Park、R.Bugiani、P.Cavanni、H.Nakajima 等人：“来自囊泡茎叶霉（欧洲梨植物褐斑病的原因）的宿主选择性 SV 毒素对梨树超微结构的影响

E.Sakuno: "A new inhibitor of 5'-hydroxyaverantin dehydrogenase, an enzyme involved in aflatoxin biosynthesis, from Trichoderma hamatum"Journal of Natural Products. 63. 1677-1678 (2000)

E.Sakuno：“一种新的 5-羟基阿维丁脱氢酶抑制剂，一种参与黄曲霉毒素生物合成的酶，来自钩状木霉”《天然产物杂志》。

H.Tani,Y.Fujii and H.Nakajjima: "Chlamydocin analogues from the soil fungus Peniophora sp.: structures and plant growth-retardant activity"Pytochemistry. (発表予定). (2001)

H. Tani、Y. Fujii 和 H. Nakajjima：“来自土壤真菌 Peniophora sp. 的衣霉素类似物：结构和植物生长抑制活性”（即将发表）。