National Oceanographic and Atmospheric Administration, National Marine Fisheries Service, Northeast Fisheries Science Center, Milford, CT 06460, USA.
Mar Environ Res. 2013 Feb;83:23-8. doi: 10.1016/j.marenvres.2012.10.005. Epub 2012 Nov 20.
The production of the toxin Domoic Acid (DA) by the diatoms Pseudo-nitzschia spp. is affected by several environmental factors, among them copper and silica. The effects of these nutrients upon DA production have been studied individually, but not in combination. There is evidence, however, that in diatoms copper can enter the cell via the silicic-acid transport site. The goal of this study was to analyze the effect of the interaction between copper and silicic-acid supply upon DA production in Pseudo-nitzschia multiseries. The study was motivated by concerns about the risk of toxigenic Pseudo-nitzschia spp. impacting mussel aquaculture in New England (USA). The results of the present study do not indicate that copper uses the silicic acid transport site to enter the cell; nevertheless, there is an interaction between these two nutrients that produces a synergistic affect upon toxin production. A small increase in copper, without a simultaneous increase in silicate, as well as an increase in both copper and silicate, leads to DA up-regulation. Furthermore, the field component of this study reports the presence of species of Pseudo-nitzschia on the New England coast that are capable of producing DA. Together these findings indicate that risk of DA impacting mussel aquaculture along the coast of New England would be increased by an unusual enrichment of copper in the vicinity of mussel farms.
产毒甲藻（Domoic Acid，简称 DA）的产生受多种环境因素的影响，其中包括铜和硅。这些营养素对 DA 产生的影响已经分别进行了研究，但尚未结合起来研究。然而，有证据表明，在硅藻中，铜可以通过硅酸运输部位进入细胞。本研究的目的是分析铜和硅供应之间的相互作用对多纹膝沟藻（Pseudo-nitzschia multiseries）产生 DA 的影响。这项研究的动机是对产毒甲藻对美国新英格兰贝类养殖的潜在风险感到担忧。本研究的结果表明，铜并不利用硅的运输部位进入细胞；然而，这两种营养素之间存在相互作用，对毒素的产生产生协同影响。铜的少量增加，而没有同时增加硅酸盐，以及铜和硅酸盐的同时增加，都会导致 DA 的上调。此外，本研究的实地部分报告了新英格兰沿海存在能够产生 DA 的假膝沟藻物种。这些发现表明，在贻贝养殖场附近铜的异常富集会增加 DA 对新英格兰沿海贝类养殖的影响风险。
