Chemical and biochemical study on venomous jellyfish proteinaceous toxins

刺胞动物门的成员（珊瑚、海葵、水母）都有刺囊（刺细胞），它们用它来捕捉猎物和防御。许多刺胞动物被认为是危险的海洋生物，因为它们的刺会产生毒性。据报道，一些水母，如Chironex fleckeri， Chropsalmus quadrigatus和Physalia Physalis的螫伤对人类是致命的。刺胞毒素已被广泛研究，其化学特征主要是蛋白质。刺胞毒素的确切化学性质尚未阐明，由于其不稳定的性质，除了一些中等稳定的海葵神经毒性多肽。最近，我们开发了一种新的从水母中分离不稳定蛋白毒素的纯化方法。该纯化方法从三种箱形水母（海黄蜂）中分离出活性蛋白毒素，分别为Carybdea rastoni、Carybdea alota和Chropslmus quadrigatus。海螺是日本游泳者和游泳者最讨厌的海洋生物之一。C. alata是夏威夷常见的毒刺。这三个物种的刺痛已被证明能引起人类皮肤疼痛和炎症。据报道，来自冲绳的四角鳗蜇伤造成3人死亡。采用RT-PCR和5'-/3'- race方法对三种水母蛋白毒素的全长核苷酸和氨基酸序列进行了分析，结果表明，三种水母蛋白毒素的同源性为22-44% （43-45 kDa）。由于这些毒素没有显示出与任何其他已知蛋白质的同源性，因此建议这些毒素代表一类新的生物蛋白酶。

Members of the phylum Cnidaria (corals, sea anemones, jellyfishes) are equipped with nemaotocysts (stinging cells) which they use in capturing prey and for defense. Many cnidarians are considered hazardous sea-creatures due to the toxicity inflicted by their sting. The sting of some jellyfishes, such as Chironex fleckeri, Chropsalmus quadrigatus and Physalia Physalis have been reported to be lethal to humans. Cnidarian toxins have been extensively studied and chemically characterized as mostly proteinaceous. The exact chemical properties of cnidarian toxins have not been elucidated due to their labile nature, except for some moderately stable neurotoxic polypeptides from sea anemones. Recently, we have developed a novel purification method for isolating unstable proteinaceous toxins from jellyfish. This purification method has resulted in the isolation of active protein toxins from three species of box jellyfishes (sea wasps), Carybdea rastoni, Carybdea alota and Chropslmus quadrigatus. C. rastoni is one of the most annoying sea-creatures for swimmers and bathers in Japan. C. alata is a common stinger in Hawaii. The sting of these three Species has been documented to induce cutaneous pain and inflammation in humans. Lt has been reported that the sting of C. quadrigatus from Okinawan resulted in three fatalities. RT-PCR and 5'-/3'-RACE methods were used to elucidate the full-length nucleotide and amino acid sequences of the isolated proteinaceous toxins from C. rastoni, C alata and C. quadrigatus Comparison between the proteinaceous toxins (43-45 kDa) from the three jellyfishes demonstrated 22-44% homology. Since these toxins did not show any homology with any other known protein, it is suggested that these toxins represent a novel class of bioastie proteins.