Microbial Genomics and Ecology, Office of Academic Research and Industry-Government Collaboration, Hiroshima University, 1-3-2 Kagamiyama, Higashi-Hiroshima City, Hiroshima, 739-8511, Japan.
Centro de Estudios de Algas Nocivas (CREAN), Instituto de Fomento Pesquero (IFOP), Padre Harter 547, 5480000, Puerto Montt, Chile.
Biometals. 2022 Feb;35(1):39-51. doi: 10.1007/s10534-021-00349-2. Epub 2021 Oct 30.
The dinoflagellate Alexandrium catenella is a well-known paralytic shellfish toxin producer that forms harmful algal blooms (HABs) worldwide. Blooms of this species have repeatedly brought severe ecological and economic impacts to Chile, especially in the southern region, where the shellfish and salmon industries are world-famous. The mechanisms of such HABs have been intensively studied but are still unclear. Nutrient overloading is one of the often-discussed drivers for HABs. The present study used the A. catenella strain isolated from southern Chile to investigate how iron conditions could affect their growth and toxin production as related to HAB. Our results showed that an optimum concentration of iron was pivotal for proper A. catenella growth. Thus, while excess iron exerted a toxic effect, low iron media led to iron insufficiency and growth inhibition. In addition, the study shows that the degree of paralytic shellfish toxin production by A. catenella varied depending on the iron concentration in the culture media. The A. catenella strain from southern Chile produced GTX1-4 exclusively in the fmol cell scale. Based on these findings, we suggest that including iron and paralytic shellfish toxin measurements in the fields can improve the current HAB monitoring and contribute to an understanding of A. catenella bloom dynamics in Chile.
链状亚历山大藻是一种众所周知的麻痹性贝类毒素生产者，它在全球范围内形成有害藻华（HAB）。该物种的水华已多次给智利带来严重的生态和经济影响，尤其是在南部地区，那里的贝类和鲑鱼产业举世闻名。这种 HAB 的机制已得到深入研究，但仍不清楚。营养过载是经常讨论的 HAB 驱动因素之一。本研究使用从智利南部分离出的链状亚历山大藻菌株，研究铁条件如何影响其生长和与 HAB 相关的毒素产生。我们的结果表明，铁的最佳浓度对链状亚历山大藻的正常生长至关重要。因此，虽然过量的铁会产生毒性作用，但低铁培养基会导致铁不足和生长抑制。此外，该研究表明，链状亚历山大藻产生麻痹性贝类毒素的程度取决于培养基中的铁浓度。来自智利南部的链状亚历山大藻菌株仅在 fmol 细胞水平上产生 GTX1-4。基于这些发现，我们建议在实地测量铁和麻痹性贝类毒素可以改进当前的 HAB 监测，并有助于了解智利的链状亚历山大藻水华动态。
