The raphidophyte Chattonella antiqua is a noxious red-tide-forming alga that harms fish culture and the aquatic environment. Chattonella antiqua produces and secretes superoxide anions (O₂⁻), and excessive secretion of O₂^– into the water has been associated with fish mortality. It is known that strong light stimulates the production of O₂^– in Chattonella spp. but the mechanism of the light-induced production of O₂^– remains to be clarified. In the present study, we examined the effects of light on extracellular levels of O₂^– and photosynthesis in C. antiqua. Extracellular levels of O₂^– rose during growth under high-intensity light, and the level of O₂^– was correlated with the photosynthetic parameter qP, which reflects the rate of transport of electrons downstream of photosystem II. The production of O₂^– was inhibited in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea, an inhibitor of photosynthetic electron transport, suggesting that reducing power derived from electron transport might be required for the production of O₂⁻. By contrast, the production of O₂^– was enhanced in the presence of glycolaldehyde, an inhibitor of the Calvin-Benson cycle, suggesting that the accumulation of NADPH might stimulate the production of O₂⁻. Thus, it is likely that the production of O₂^– is regulated by photosynthesis in C. antiqua.

蝴蝶藻属Chattonella antiqua是一种有害的形成红潮的藻类，危害鱼类的养殖和水生环境。卡盾蝇生成和分泌超氧阴离子（O ₂ ^- ），和的O-分泌过多₂ ^-入水已经与鱼的死亡率。已知强光刺激产生的O ₂ ^-在卡盾藻属。但光致生产的O的机构₂ ^-仍有待阐明。在本研究中，我们检测的光上的O外水平的影响₂ ^-中和光合作用C. antiqua。细胞外的O ₂ ^–在高强度光下生长期间上升，而O ₂ ^–的水平与光合作用参数qP相关，该参数反映了电子在光系统II下游的传输速率。在光合电子传输抑制剂3-（3,4-二氯苯基）-1,1-二甲基脲的存在下，O ₂ ^–的产生被抑制，这表明降低电子传递所产生的功率可能需要Ø ₂ ^- 。相比之下，O _2的产生^–在乙醇醛，卡尔文·本森循环的抑制剂的存在下增强，这表明NADPH的积累可能会刺激产生的O ₂ ^- 。因此，很可能O ₂ ^–的产生受古埃及念珠菌中光合作用的调节。