首页> 外文期刊>Chromatographia >CZE of sulfur-containing amino acids and peptides and its application to the quantitative study of heavy metal-caused thiol oxidations
【24h】

CZE of sulfur-containing amino acids and peptides and its application to the quantitative study of heavy metal-caused thiol oxidations

机译:含硫氨基酸和肽的CZE及其在重金属引起的巯基氧化反应定量研究中的应用

获取原文
获取原文并翻译 | 示例
           

摘要

The redox-active, sulfur-containing amino acids cysteine and methionine, the tripeptide glutathione and their oxidized counterparts cystine, methionine sulfoxide, and glutathione disulfide were separated as anions by capillary zone electrophoresis (CZE) in a 72 cm long fused silica capillary filled with 100 mM phosphate buffer, pH 8.0, at a voltage of +30 kV in 20 min. The optimized CZE method was suited for the implementation of quantitative metal interaction studies of the biomolecules in a biologically relevant concentration range (μM-mM). Decreasing peak areas of the reduced forms of cysteine and glutathione and simultaneously increasing peak areas of the oxidized forms after incubation of the reduced biomolecules with divalent heavy metal cations indicated redox reactions which could be responsible for toxic metal actions in biological systems. CZE measurements revealed that a 50 % oxidation grade of cysteine was achieved at a molar metal:cysteine ratio of 0.85 in case of Zn(II) addition and of 0.11 in case of Cu(II) addition, respectively. Cu(II) oxidized 50 % of the initial glutathione at a molar Cu:peptide ratio of 0.036, whereas the 50 % oxidation grade was not reached after incubation with Co(II) up to a molar ratio of Co:peptide of 0.25.
机译:氧化还原活性的含硫氨基酸半胱氨酸和蛋氨酸,三肽谷胱甘肽及其氧化的胱氨酸,甲硫氨酸亚砜和谷胱甘肽二硫化物通过毛细管区带电泳(CZE)在72 cm长的熔融石英毛细管中分离为阴离子。 100 mM磷酸盐缓冲液,pH 8.0,在+30 kV的电压下在20分钟内。优化的CZE方法适合在生物学相关浓度范围(μM-mM)中对生物分子进行定量金属相互作用研究。在将还原的生物分子与二价重金属阳离子一起孵育后,还原型半胱氨酸和谷胱甘肽的峰面积减少,同时氧化形式的峰面积增加,这表明氧化还原反应可能是生物系统中有毒金属作用的原因。 CZE测量显示,在添加锌(II)的情况下,金属与半胱氨酸的摩尔比分别为0.85和在添加铜(II)的情况下为0.11时,实现了50%的氧化度的半胱氨酸。 Cu(II)以0.036的Cu:肽摩尔比氧化了50%的初始谷胱甘肽,而与Co(II)孵育直至Co:肽的摩尔比为0.25时,氧化程度达50%。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号