Yoshida Mireiyu, Sone Seiji, Shiomi Kazuo
Department of Food Science and Technology, Tokyo University of Marine Science and Technology, Konan-4, Minato-ku, Tokyo 108-8477, Japan.
Protein J. 2008 Dec;27(7-8):450-4. doi: 10.1007/s10930-008-9155-y.
Although eels are well known to contain toxins in the serum, their chemical properties have remained to be clarified for a long time. In this study, a proteinaceous toxin was purified from the serum of Japanese eel Anguilla japonica by anion-exchange HPLC, hydroxyapatite HPLC and gel filtration HPLC. The toxin was lethal to both mice and crabs; the LD(50) of the purified toxin against mice (intravenous injection) and crabs (injection into body cavity) were estimated to be 670 and 450 mug kg(-1), respectively. Chemical analysis data revealed that the toxin is a monomeric simple protein with a molecular mass of 100 kDa and an isoelectric point of 6.1. Three of the peptide fragments produced by digestion of the purified toxin with lysylendopeptidase were sequenced. However, a database search based on the determined partial amino acid sequence failed to find any proteins sharing homology with the A. japonica serum toxin.
尽管鳗鱼血清中含有毒素广为人知，但它们的化学性质长期以来一直有待阐明。在本研究中，通过阴离子交换高效液相色谱、羟基磷灰石高效液相色谱和凝胶过滤高效液相色谱从日本鳗鲡血清中纯化出一种蛋白质毒素。该毒素对小鼠和螃蟹均具有致死性；纯化毒素对小鼠（静脉注射）和螃蟹（体腔注射）的半数致死量（LD50）分别估计为670和450μg kg-1。化学分析数据表明，该毒素是一种单体简单蛋白质，分子量为100 kDa，等电点为6.1。对用赖氨酰内肽酶消化纯化毒素产生的三个肽片段进行了测序。然而，基于所确定的部分氨基酸序列在数据库中搜索未发现与日本鳗鲡血清毒素具有同源性的任何蛋白质。
