Purification and characterization of photosensitizing hemolytic toxin from harmful red tide phytoplankton, Heterocapsa circularisquama
Purification and characterization of photosensitizing hemolytic toxin from harmful red tide phytoplankton, Heterocapsa circularisquama
复制标题
DOI：
10.1016/j.aquatox.2005.04.005
复制
发表时间：
2005-07-30
影响因子：
4.5
通讯作者：
Oda, T
中科院分区：
文献类型：
--
作者：
Miyazaki, Y;Nakashima, T;Oda, T
我们以前发现，从Heterocapsa circulatum quaina，一种有害的红脊甲藻，制备的甲醇提取物，显示光依赖性溶血活性对兔红细胞。有趣的是，提取物对HeLa细胞的细胞毒性也严格依赖于光，即使在黑暗中在非常高的浓度下也没有观察到显著的毒性作用。在本研究中，通过几种色谱程序纯化了浸提液中存在的溶血剂。最终的HPLC分析显示，存在至少两种具有不同保留时间的溶血毒素（H2-a和113-a），其具有相似的吸收光谱。虽然113-a级分被痕量的H2-a污染，但H2-a级分在三维色谱图上给出单峰。快原子轰击（FAB）-质谱（MS）和电喷雾电离四极杆飞行时间（ESI Q-TOF）质谱分析结果表明，H2-a的分子量为566。由于核磁共振分析表明H2-a分子中存在吡咯环，因此H2-a可能是具有与焦脱镁叶绿酸a甲酯（一种众所周知的光敏溶血化合物）类似结构的卟啉衍生物。然而，H2-a和焦脱镁叶绿酸a甲酯之间观察到一些结构和物理化学差异。由于H2-a对HeLa细胞具有浓度依赖性的光敏细胞毒性以及溶血活性，因此H2-a可能是具有光敏溶血细胞毒性的新型卟啉衍生物。(c)2005 Elsevier B. V.保留所有权利。
We have previously found that the methanol extract prepared from Heterocapsa circularisquaina, a harmful red rid dinoflagellate, showed light-dependent hemolytic activity toward rabbit erythrocytes. Interestingly, the cytotoxicity of the extract against HeLa cells was also strictly light-dependent, and no significant toxic effect was observed even at very high concentration in the dark. In this study, the hemolytic agents present in the extract were purified by several chromatographic procedures. Final HPLC analysis revealed that there are at least two hemolytic toxins with different retention times (H2-a and 113-a), which have similar absorption spectra. Although 113-a fraction was contaminated by a trace amount of H2-a, H2-a fraction gave a single peak on a three-dimensional chromatogram. The results of fast atom bombardment (FAB)-mass spectrometry (MS) and electrospray ionization quadrupole time-of-flight (ESI Q-TOF) mass spectrometry analyses suggested that the molecular weight of H2-a was 566. Since nuclear magnetic resonance analysis indicated the presence of a pyrrole ring in H2-a molecule, H2-a may be a porphyrin derivative with similar structure of pyropheophorbide a methyl ester, a well-known photosensitizing hemolyfic compound. However, some structural and physicochemical differences were observed between H2-a and pyropheophorbide a methyl ester. Since H2-a showed potent photosensitizing cytotoxicity toward HeLa cells in a concentration-dependent manner as well as hemolytic activity, H2-a may be a novel porphyrin derivative with photosensitizing hemolytic cytotoxicity. (c) 2005 Elsevier B.V. All rights reserved.