Bioaccumulation of methylmercury in a marine diatom and the influence of dissolved organic matter.
Bioaccumulation of methylmercury in a marine diatom and the influence of dissolved organic matter.
复制标题
甲基汞在海洋硅藻中的生物累积以及溶解有机物的影响。
DOI：
10.1016/j.marchem.2017.09.005
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发表时间：
2017
期刊：
影响因子：
3
通讯作者：
Fisher,NicholasS
中科院分区：
文献类型：
--
作者：
Lee,Cheng-Shiuan;Fisher,NicholasS
大多数金属（包括甲基汞（MeHg））在水生生物群中最大的生物富集步骤是从水到浮游植物，但溶解有机物（DOM）对甲基汞这一过程的影响程度在海洋系统中很大程度上仍未被探索。本研究调查了特定含硫有机化合物和天然存在的 DOM 对海洋硅藻假海链藻 (Thalassiosira fakenana) 中甲基汞积累的影响。计算甲基汞的初始吸收速率常数和体积浓度因子 (VCF)，以评估在一系列有机化合物浓度存在下藻细胞中甲基汞的富集情况。在环境实际浓度和较高浓度下，添加甘氨酸和蛋氨酸对藻类 MeHg 吸收没有影响，但半胱氨酸和巯基乙酸等含硫醇化合物在高添加浓度（比天然浓度高 100 倍以上）下减少了藻类细胞中 MeHg 的积累。然而，谷胱甘肽（另一种含硫醇化合物）的环境实际浓度低至 10 nM，导致 VCF 下降约 30%，这表明它在天然水中可能很重要。添加 0.1 和 0.5 mg C/L 的腐植酸也分别使 MeHg VCF 降低约 15% 和约 25%。 MeHg forT 的生物累积。具有不同水平溶解有机碳 (DOC) 的拟南海沿海水域与总体 DOC 浓度呈负相关。一般来说，天然存在的 DOM，特别是某些含硫醇的化合物，可以减少浮游植物对 MeHg 的吸收。
The largest bioconcentration step of most metals, including methylmercury (MeHg), in aquatic biota is from water to phytoplankton, but the extent to which dissolved organic matter (DOM) affects this process for MeHg largely remains unexplored in marine systems. This study investigated the influence of specific sulfur-containing organic compounds and naturally occurring DOM on the accumulation of MeHg in a marine diatom Thalassiosira pseudonana. Initial uptake rate constants and volume concentration factors (VCFs) of MeHg were calculated to evaluate MeHg enrichment in algal cells in the presence of a range of organic compound concentrations. At environmentally realistic and higher concentrations, the addition of glycine and methionine had no effect on algal MeHg uptake, but thiol-containing compounds such as cysteine and thioglycolic acid reduced MeHg accumulation in algal cells at high added concentrations (> 100 times higher than naturally occurring concentrations). However, environmentally realistic concentrations of glutathione, another thiol-containing compound as low as 10 nM, resulted in a decline of ~ 30% in VCFs, suggesting its possible importance in natural waters. Humic acid additions of 0.1 and 0.5 mg C/L also reduced MeHg VCFs by ~ 15% and ~ 25%, respectively. The bioaccumulation of MeHg forT. pseudonanain coastal waters with varying levels of dissolved organic carbon (DOC) was inversely correlated with bulk DOC concentrations. Generally, naturally occurring DOM, particularly certain thiol-containing compounds, can reduce MeHg uptake by phytoplankton.
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影响因子：
8.3
作者：
Mason RP;Choi AL;Fitzgerald WF;Hammerschmidt CR;Lamborg CH;Soerensen AL;Sunderland EM
通讯作者：
Sunderland EM
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影响因子：
3
作者：
L. M. Laglera;C. V. D. Berg
通讯作者：
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影响因子：
11.4
作者：
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通讯作者：
D. Armstrong
海水介质中质子化半胱氨酸的解离常数
影响因子：
3
作者：
V. Sharma;A. Moulin;F. Millero;C. Stefano
通讯作者：
C. Stefano
影响因子：
4.5
作者：
Dupont, CL;Ahner, BA
通讯作者：
Ahner, BA