Studies on Bacteria Which Produce Paralytic Shellfish Toxins.

产生麻痹性贝类毒素的细菌的研究。

基本信息

批准号：
63470121
负责人：
KODAMA Masaaki
金额：
$ 4.42万
依托单位：
Kitasato University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

项目摘要

In Ofunato Bay, the shellfish toxicity has been often observed to increase under absence of toxic dinoflagellates. This phenomenon suggests the presence of unknown causative organism (S). Recently, we have found that a bacterium Moraxella sp. isolated from Alexandrium tamarense produces paralytic shellfish toxins (PSP toxins). Thus the link of this bacterium with shellfish toxicity was examined. Analysis of PSP toxins in the particle fractions with different sizes collected from the seawater during the period when the shellfish toxicity increased under absence of toxic dinoflagellate showed that particles with bacterial size possess significant amount of PSP toxins, the profile of which was similar to that of shellfish and dinoflagellate. Moraxella sp. was also detected in the seawater. These findings show the presence of PSP toxins producing bacteria in the ocean that are possibly linked with shellfish toxicity. These also suggest that toxin productivity of the bacteria increases under nutrient poor conditions. Thus Moraxella sp. Was cultured under nutrient poor conditions. Its toxin productivity increased when it was cultured in the natural seawater and left for 10 days, indicating that it produces toxins under starved conditions. PSP toxins producing bacteria were screened in various species of toxic dinoflagellates. Almost all the dinoflagellates gave the intracellular bacteria which showed toxin productivity. These facts support the idea that intracellular bacteria are necessary for the toxin production of dinoflagellates. Bacterial species found in the toxic dinoflagellates were specific to strains as well as species of dinoflagellate, showing the wide distribution of these bacteria. PSP toxins which seemed to originate from bacteria were detected in the bivalves collected from the areas where no dinoflagellates bloom.

在大船渡湾，经常观察到贝类毒性在没有有毒甲藻的情况下增加。这种现象表明存在未知的致病微生物（S）。最近，我们发现了一种细菌莫拉氏菌（Moraxella sp.）。从塔玛亚历山大藻中分离出来的藻会产生麻痹性贝类毒素（PSP 毒素）。因此检查了这种细菌与贝类毒性的联系。在没有有毒甲藻的情况下，贝类毒性增加期间，对从海水中收集的不同尺寸的颗粒部分中的PSP毒素进行了分析，结果表明，具有细菌尺寸的颗粒具有大量的PSP毒素，其谱与贝类和甲藻。莫拉氏菌属海水中也被检测到。这些发现表明海洋中存在产生 PSP 毒素的细菌，这些细菌可能与贝类毒性有关。这些还表明，在营养不良的条件下，细菌的毒素生产力会增加。因此莫拉氏菌属。在营养不良的条件下培养。当它在天然海水中培养并放置10天时，其毒素生产力增加，表明它在饥饿条件下产生毒素。在各种有毒甲藻中筛选了产生 PSP 毒素的细菌。几乎所有甲藻都产生具有毒素生产力的细胞内细菌。这些事实支持这样的观点：细胞内细菌对于甲藻毒素的产生是必需的。在有毒甲藻中发现的细菌物种是菌株和甲藻物种所特有的，表明这些细菌分布广泛。在从没有甲藻繁殖的地区收集的双壳类动物中检测到了似乎源自细菌的 PSP 毒素。