Molecular mechanism of chemical self-defense of the protozoan ciliates.

原生动物纤毛虫化学自卫的分子机制。

• 批准号: 16310154
• 负责人: IIO Hideo
• 金额: $ 9.92万
• 依托单位: Osaka City University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16310154/
• 关键词: chemical self-defense; ciliate; blepharismin; spirostomin; structural determination; Blepharisma japonicum; Spirostomum teres; ロキソデス; ケロノプシン; クリマコストール

In the continuing study on predator-prey interaction between ciliates, we reported the isolation and structural determination of a defense toxin climacostol from a heterotrich ciliate Climacostomum virens. On the preliminary study of the predator-prey interaction between ciliates Dileptus margaritifer as a predator and Spirostomum teres an another heterotrich ciliate as a prey, we observed elusive behavior of S.teres from the predator and the presence of the cortical vesicle in S.teres just beneath the cell membrane, which suggested that S.teres had some toxic substance against the predator. We report the isolation and structural determination of a toxic substance spirortomin from S.teres.The whole cells of S.teres were dipped in aqueous 70% EtOH. After removal of the cells by filtration and concentration of the solvent, the residue was partitioned between ethyl acetate and water. From the organic layer, an active fraction based on lethal toxicity against a ciliate Paramecium caudatum … More was obtained by chromatography on silica gel eluted with 1.5% Me0H/CH_2C_<12> (Rf value 0.44). The fraction contained a new compound spirostomin (1), whose molecular formula was estimated to be C_<16>H_<14>O_5 by HREIMS and ^1H and ^<13>C NMR. Based on ^1H, ^<13>C NMR and UV spectra, the structure of spirostomin was established as spiro[(2,5-dimethy1-5,6,7,8-tetrahydronaphtalene-1,4-dione)-8,6'- (pyrane-2',5'-dione)], a spiro compound having a carbon framework hitherto unknown. The relative stereochemistry of spirostomin was established by the total synthesis of spirostomine A and B. The absolute chemistry of spirostomine was also estimated by the CD spectra and the result based on the DFT calculation.Blepharismins, toxic pigments of the ciliate Blepharisma japonicum, are polycyclic ring-condensed compounds. Assignment of ^<13>C NMR signals for blepharismin C, a major constituent of blepharismins, was achieved by analyses of the HMQC, HMBC, and INADEQUATE spectra of 13C-enriched samples obtained by feeding experiments using sodium [1-13C], [2-13C], and [1,2-^<13>C2]acetates. Less

在对纤毛虫捕食-食饵相互作用的持续研究中，我们报道了从异养纤毛虫（Climacostomum virens）中分离和鉴定一种防御毒素climacostol的结构。在初步研究了作为捕食者的玛格丽蒂Dileptus marmartifer与作为捕食者的异养纤毛虫圆螺（Spirostomum teres）之间的捕食-食饵相互作用时，我们观察到圆螺对捕食者的难以捉摸的行为以及圆螺细胞膜下皮层囊泡的存在，这表明圆螺对捕食者具有一定的毒性物质。本文报道了从螺旋体中分离出一种有毒物质螺蛋白，并对其结构进行了测定。通过过滤和溶剂浓缩去除细胞后，残留物在乙酸乙酯和水之间分割。在有机层中，用1.5% Me0H/CH_2C_<12> （Rf值0.44）洗脱的硅胶层析得到了对尾状草草虫（Paramecium caudatum…More）致死毒性的活性组分。经hrems和^1H和^<13>C核磁共振鉴定，其分子式为C_<16>H_<14>O_5。根据^1H， ^<13>C核磁共振光谱和紫外光谱，确定了螺旋蛋白的结构为螺旋[（2,5-二甲基- 1,5,6,7,8 -四氢萘-1,4-二酮）-8,6'- （pyrane-2',5'-二酮）]，是一种碳骨架未知的螺旋化合物。通过全合成螺口碱A和b，建立了螺口碱的相对立体化学，并通过CD谱和DFT计算结果估计了螺口碱的绝对化学性质。blepharmins是纤毛虫blepharma japonicum的有毒色素，是一种多环环缩合化合物。ble法利赛明的主要成分ble法利赛明C的^<13>C核磁共振信号的分配是通过分析HMQC， HMBC和通过使用钠[1- 13c]， [2- 13c]和[1,2-^<13>C2]醋酸盐进行的实验获得的13c富集样品的不充分光谱来实现的。少