Piechalak Aneta, Tomaszewska Barbara, Barałkiewicz Danuta
Department of Biochemistry, A. Mickiewicz University, Fredry 10, 61-701 Poznań, Poland.
Phytochemistry. 2003 Dec;64(7):1239-51. doi: 10.1016/s0031-9422(03)00515-6.
The aim of our research was to demonstrate how the presence of EDTA affects resistance of pea plants to Pb and Pb-EDTA presence, and to show the effectivity of lead ions accumulation and translocation. It was determined that EDTA not only increased the amount of Pb taken up by plants but also Pb ion transport through the xylem and metal translocation from roots to stems and leaves. It can be seen in the presented research results that addition of the chelator with Pb limited metal phytotoxicity. We also demonstrated a significant effect of EDTA not only on Pb accumulation and metal transport to the aboveground parts but also on the profile and amount of thiol compounds: glutathione (GSH), homoglutathione (hGSH) or phytochelatins (PCs), synthesized by the plants. We observed a significant effect of the synthetic chelator on increasing the level of Pb accumulation in roots of plants treated with Pb including EDTA (0.5 and 1 mM). Pisum sativum plants treated only with 1 mM Pb(NO3)2 accumulated over 50 mg Pb x g(-1) dry wt during 4 days of cultivation. Whereas in roots of pea plants exposed to Pb+0.5 mM EDTA 35% more Pb was observed. When 1 mM EDTA was applied roots of pea accumulated over 67% more metal. The presence of EDTA also increased metal uptake and transport to the aboveground parts. In pea plants treated only with 1 mM lead nitrate less than 3 mg Pb x g(-1) dry wt was transported, whereas in P. sativum treated with Pb-EDTA doubled amount of Pb was observed in stems and leaves.
我们研究的目的是证明乙二胺四乙酸（EDTA）的存在如何影响豌豆植株对铅以及铅 - EDTA存在情况下的抗性，并展示铅离子积累和转运的有效性。已确定EDTA不仅增加了植物吸收的铅量，还增加了铅离子通过木质部的运输以及从根到茎和叶的金属转运。从所呈现的研究结果可以看出，添加螯合剂与铅可限制金属的植物毒性。我们还证明了EDTA不仅对铅的积累和向地上部分的金属运输有显著影响，而且对植物合成的硫醇化合物：谷胱甘肽（GSH）、高半胱氨酸（hGSH）或植物螯合肽（PCs）的分布和数量也有显著影响。我们观察到合成螯合剂对增加用含EDTA（0.5和1 mM）的铅处理的植物根部铅积累水平有显著影响。仅用1 mM硝酸铅处理的豌豆植株在培养4天期间积累了超过50 mg Pb x g(-1)干重的铅。而在暴露于Pb + 0.5 mM EDTA的豌豆植株根部，观察到的铅含量多35%。当施用1 mM EDTA时，豌豆根部积累的金属多67%以上。EDTA的存在还增加了金属向地上部分的吸收和运输。仅用1 mM硝酸铅处理的豌豆植株中，运输的铅少于3 mg Pb x g(-1)干重，而在用Pb - EDTA处理的豌豆中，茎和叶中的铅含量增加了一倍。
