Mechanism and significance of generation of reactive oxygen by red tide plankton, Chattonella

Chattonella marina是一种针形藻类，是赤潮中毒性最强的浮游植物之一，对鱼类尤其是黄尾五斑海鲫具有很高的毒性。虽然确切的机制的毒性作用或查顿氏菌属物种仍不清楚，它已被证明，在氧分压或动脉血的减少是最早的生理障碍，在鱼暴露于C.海洋后观察到。对暴露于C.marina的鱼的生理和组织学研究也表明，由过量粘液引起的通过鳃板的呼吸水流的阻塞干扰了O2转移，导致窒息。最近的研究表明，查顿氏菌产生活性氧（ROS），如O2-、H2 O2和羟基自由基（OH）。此外，据报道，也被归类为针藻类的赤潮异弯藻产生ROS，并且对虹鳟、虹鳟表现出氧自由基介导的毒性作用 ...更多信息 我的吻因此，ROS的产生可能是针藻鞭毛虫的共同特征。这一观点得到了我们最近的研究结果的支持，在这些研究中，其他的针藻类鞭毛虫如Olisthodiscus luteus和Fibrocapsa japonica产生O2-和H2 O2。因为有害的影响或氧自由基已被很好地记录。Chattonella sp.产生的活性氧可能是造成鳃组织损伤的原因。有趣的是，最近的研究结果表明，活性氧的产生是由凝集素，如刀豆素A，CBH，WGH刺激，表明细胞表面的氧化还原酶可能参与O2-的产生，这种酶是负责凝集素刺激。此外，从黄尾鱼、真鲷和日本比目鱼的皮肤和鳃制备的鱼粘液以浓度依赖的方式刺激C.marina和H.akashiwo产生增加的O2-。这些结果表明，鱼粘液增强了活性氧介导的查顿氏菌对鱼类的毒性作用。少

Chattonella marina, a raphidophycean flagellate, is one of the most noxious red tide phytoplankton and is highly toxic to fish, especially to yellowtail Seriola quinqueradiata. Although the precise mechanism of the toxic action or Chattonella sp.remains unclear, it has been demonstrated that a decrease in oxygen partial pressure or arterial blood is the earliest physiological disturbance observed in fish after exposure to C.marina. Physiological and histological studies of fish exposed to C.marina also suggested that the blockade of respiratory water flow through the gill lamellae caused by excessive mucus interferes with O2 transfer, resulting in asphyxia. Recent studies have shown that Chattonella sp.generates reactive oxygen species (ROS) such as O2-, H2O2, and hydroxyl radical (OH). Furthermore, it has been reported that Heterosigma akashiwo, which is also classified in a raphidophycean, produces ROS,and showed an oxygen-radical-mediated toxic effect on rainbow trout, Oncorhynchus … More mykiss. Thus, it is likely that the production of ROS is a common feature of raphidophycean flagellates. This notion is supported by our recent findings in which other raphidophycean flagellates such as Olisthodiscus luteus and Fibrocapsa japonica produce O2-and H2O2. Since harmful effects or oxygen radicals have been well documented. ROS generated by Chattonella sp.may be responsible for gill tissue injury. Interestingly, resent results domonstrated that the generation of ROS by Chattonella is stimulated by lectins such as Con A,CBH,and WGH,suggesting that cell-surface redox enzyme may be involved in O2-production, and such enzyme is responsible for the lectin-stimulation. Furthermore, Fish mucus prepared from skin and gill of yellowtail, red sea bream, and japanese flounder stimulated C.marina and H.akashiwo to generate increased amounts or O2-in a concentration dependent manner. These results suggest that fish mucus enhances the ROS mediated toxic effects of Chattonella against fish. Less