A study on ASP toxin production mechanism in diatom

硅藻ASP产毒机制研究

• 批准号: 17580182
• 负责人: KOTAKI Yuichi
• 金额: $ 2.3万
• 依托单位: Kitasato University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17580182/
• 关键词: Amnesic shellfish poisoning; domoic acid; Pseudo-nitzschia multiseries; Nitzschia navis-varingica; diatom; isodomoic acid; iron; bacteria

Domoic acid (DA) production by bacteria itself was investigated in Pseudo-nitzschia multiseries culture. Non-axenic cell-free medium prepared from 1-or 3-week culture was further cultured for 5 weeks under the same conditions. No DA production was observed during the entire culture period, suggesting that bacteria itself does not produce DA even in P multiseries culture that shows high level of DA. DA production of axenic culture was investigated when cultured in non-axenic P multiseries culture separating with dialysis membrane (m. w 50,000 cut off). Before 3-week, axenic culture cells showed no or trace amount of DA. After 3-week, DA content of axenic cells increased significantly. DA contents were comparable to that of non-axenic cells, suggesting that DA production of axenic cells occurred in association with some compounds smaller than m. w. 50,000 came from non-axenic culture. Nitzschia navis-varingica culture was examined for DA production and iron uptake. DA content of the diatom cells increased as the iron content of the cells increased during the stationary growth phase, suggesting that DA might be produced in association with the uptake of insoluble iron as in case of P. multiseries. X navis-varingica isolated from the Philippines was confirmed to produce not only DA but also isodomoic acids A (IA) and B (TB). Isolates from only 3 limited areas produced IA and IB instead of DA. Many other isolates from other places produced DA and IB. ASP toxin composition of N. navis-varingica was investigated outside the Philippines, resulting in confirmation that many N. navis-varingica produces DA and TB and only limited isolates described above produces IA and TB. Toxin composition in non-axenic sub-strain was stable, but one axenic sub-strain changed its original toxin composition DA-IB to IA-TB, suggesting that some bacteria or combination of bacteria might effect the toxin composition of N navis-varingica.

在拟菱形藻多系列培养条件下，对细菌自身产生软骨藻酸进行了研究。将培养1周或3周制备的非无菌无细胞培养液在相同条件下继续培养5周。在整个培养过程中没有观察到DA的产生，这表明即使在显示高DA水平的P多系列培养中，细菌本身也不产生DA。用透析膜分离的非无菌P系列培养物培养时，研究了无菌培养物DA的产生。培养3周前，无菌培养细胞未见或有微量DA存在。培养3周后，无菌细胞DA含量显著增加。DA含量与非无菌细胞相当，表明无菌细胞DA的产生与一些小于mw的化合物有关，50000来自非无菌培养。研究了纳氏菱形藻培养过程中DA的产生和铁的吸收。在生长稳定期，随着细胞含铁量的增加，硅藻细胞的DA含量也随之增加，这表明DA的产生可能与多系列磷细菌对不溶性铁的吸收有关。从菲律宾分离的X navis-varingica不仅能产生DA，而且还能产生同种异形酸A(IA)和B(TB)。仅有3个有限地区的菌株产生IA和IB，而不产生DA。许多其他地方的分离株产生DA和IB。在菲律宾以外的地方对海军新冠夜蛾的天冬氨酸毒素组成进行了调查，结果证实，许多海军新冠夜蛾产生DA和TB，只有上述有限的分离株产生IA和TB。非无菌亚株的毒素组成稳定，但有一株无菌亚株的毒素组成由原来的DA-IB变为IA-TB，这可能是某些细菌或细菌组合影响了海军陆战队的毒素组成。

项目成果

Screening of diatoms that produce domoic acid and its derivatives in the Philippines.

菲律宾生产软骨藻酸及其衍生物的硅藻的筛选。

• 发表时间: 2006
• 期刊: Coastal Marine Science 30
• 作者: Ryu;S. ;Kashiwagi;M;柏 雅之;柏 雅之;柏 雅之(共著);柏 雅之;柏 雅之;Takeda S.;Kondo Y.;Lundholm N;Kotaki Y;Bajarias FF
• 通讯作者: Bajarias FF

Analytical method for domoic acid in shellfish.

贝类中软骨藻酸的分析方法。

• 发表时间: 2005
• 期刊: Hand Book of the Analyses for Food Safety, Japan Food Hygiene Association, Tokyo. (In Japanese).
• 作者: Bajarias F.F.A.;Kotaki Y.et al.;Kotaki Y;Lundholm N;Kotaki Y.;Lundholm N.;Takeda S.;Masaaki.Kodama.
• 通讯作者: Masaaki.Kodama.

Distribution and speciation of dissolved iron in the Sulu Sea and its adjacent waters

• DOI: 10.1016/j.dsr2.2006.08.019
• 发表时间: 2007-01-01
• 期刊: DEEP-SEA RESEARCH PART II-TOPICAL STUDIES IN OCEANOGRAPHY
• 影响因子: 3
• 作者: Kondo, Yoshiko;Takeda, Shigenobu;Furuya, Ken
• 通讯作者: Furuya, Ken

New stage of the study on domoic acid-producing diatoms-A finding of Nitzschia navis-varingica that produces domoic acid derivatives as major toxin components.

产软骨藻酸的硅藻研究新阶段——发现菱形藻能产生软骨藻酸衍生物作为主要毒素成分。

• 发表时间: 2006
• 期刊: Coastal Marine Science 30(in press)
• 作者: Lundholm;N.;Dao Viet Ha;Takeda S.;Kotaki et al.
• 通讯作者: Kotaki et al.

ASP toxins of pennate diatoms and bacterial effects on the variation in toxin composition.

羽状硅藻的 ASP 毒素和细菌对毒素成分变化的影响。

• 期刊: Proceeding of the 12^<th> International Conference on Harmful Algae (in press)
• 作者: Boyd P.W.;Strzepek R.;Takeda S.et al.;Kotaki Y
• 通讯作者: Kotaki Y