Technische Universität Berlin, Institute of Ecology, Department Ecological Impact Research and Ecotoxicology, Ernst-Reuter-Platz 1, 10587 Berlin, Germany.
Ecotoxicol Environ Saf. 2014 Jun;104:127-31. doi: 10.1016/j.ecoenv.2014.01.039. Epub 2014 Mar 25.
In order to study the uptake of the cyanobacterial neurotoxin β-N-methylamino-l-alanine (BMAA) into the crop plant Triticum aestivum during germination and primary growth imbibed grains and 7-day-old seedlings were irrigated with 100 and 1000µg l(-1) BMAA for 4 days and 100µg l(-1) BMAA for 28 days. Content of derivatized free and protein-associated BMAA in seedlings, root and shoot tissue, respectively, were analyzed by LC-MS/MS. Free BMAA was only detected in seedlings exposed to 1000µg l(-1) BMAA, whereas protein-associated BMAA was found at both exposure concentrations. Irrigation with 100µgl(-1) BMAA led to an uptake of the neurotoxin into roots and shoots and to immediate protein-association. In roots, protein-associated BMAA was detectable after 5 days with peaking amounts after 14 days. Longer exposure did not cause further accumulation in roots. In contrast, protein-associated BMAA was detected in shoot samples after only 1 day. In shoots the highest amounts of protein-associated BMAA were found after 28 days. In turn, in both plant compartments free BMAA was below the measurable concentration.
为了研究蓝藻神经毒素β-N-甲基氨基-l-丙氨酸（BMAA）在小麦发芽和初生生长过程中的吸收情况，用 100 和 1000μg l(-1) 的 BMAA 分别对吸胀的籽粒和 7 天龄的幼苗进行了 4 天和 28 天的灌溉，用 100μg l(-1) 的 BMAA 进行了 28 天的灌溉。通过 LC-MS/MS 分析了幼苗、根和茎组织中衍生的游离和蛋白结合的 BMAA 含量。只有在暴露于 1000μg l(-1) BMAA 的幼苗中检测到游离的 BMAA，而在两种暴露浓度下均发现了蛋白结合的 BMAA。用 100µgl(-1) 的 BMAA 进行灌溉导致神经毒素被吸收到根和茎中，并立即与蛋白质结合。在根中，蛋白结合的 BMAA 在 5 天后即可检测到，在 14 天后达到峰值。更长时间的暴露不会导致根部进一步积累。相比之下，仅在 1 天后就能在茎样中检测到蛋白结合的 BMAA。在茎中，在 28 天后发现了最高量的蛋白结合的 BMAA。相反，在这两个植物部位中，游离的 BMAA 含量均低于可测浓度。
