Glutathione peroxidase inhibitory assay for electrophilic pollutants in diesel exhaust and tobacco smoke.
Glutathione peroxidase inhibitory assay for electrophilic pollutants in diesel exhaust and tobacco smoke.
复制标题
DOI：
10.1007/s00216-012-5823-z
复制
发表时间：
2012-04
影响因子：
4.3
通讯作者：
Delfino, Ralph J.
中科院分区：
文献类型：
--
作者：
Staimer, Norbert;Nguyen, Tran B.;Nizkorodov, Sergey A.;Delfino, Ralph J.
我们开发了一种快速动力学生物测定法，证明丙烯醛、巴豆醛和对苯醌等有机亲电子污染物对谷胱甘肽过氧化物酶 1 (GPx-1) 的抑制作用，这些污染物经常作为烟草烟雾、柴油机尾气和其他燃烧源的成分被发现。在一种补充方法中，我们应用高分辨率质子转移反应飞行时间质谱仪（PTR-ToF-MS）来实时监测香烟烟雾中亲电子挥发性羰基的产生。新的生物测定法使用重要的抗氧化剂硒酶 GPx-1（固定在 96 孔微量滴定板上）作为探针。该酶催化位点的硒代半胱氨酸亚基被视为半胱氨酸类似物，并且容易受到具有共轭羰基系统的化合物的亲电子攻击。将 GPx-1 固定到微量滴定板孔中，在与亲电化学品或不同来源的空气样品的水提取物一起孵育后，可以轻松去除过量的反应性抑制化合物。将香烟烟雾和柴油机尾气颗粒提取物的抑制反应与一组亲电羰基和芳基化对苯醌的化学标准进行比较。毫摩尔浓度的高反应性亲电化学物质（包括丙烯醛、乙二醛、甲基乙二醛和对苯醌）以及柴油和香烟烟雾的提取物直接使 GPx-1 活性失活。我们得出的结论是，空气污染物成分产生氧化应激的潜力可能部分是由于参与胞质抗氧化防御的酶的亲电子衍生共价修饰的结果。
We developed a rapid kinetic bioassay demonstrating the inhibition of glutathione peroxidase 1 (GPx-1) by organic electrophilic pollutants such as acrolein, crotonaldehyde, and p-benzoquinone that are frequently found as components of tobacco smoke, diesel exhaust, and other combustion sources. In a complementary approach, we applied a high-resolution proton-transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS) to monitor in real-time the generation of electrophilic volatile carbonyls in cigarette smoke. The new bioassay uses the important antioxidant selenoenzyme GPx-1, immobilized to 96-well microtiter plates, as a probe. The selenocysteine bearing subunits of the enzyme's catalytic site are viewed as cysteine analogues and are vulnerable to electrophilic attack by compounds with conjugated carbonyl systems. The immobilization of GPx-1 to microtiter plate wells enabled facile removal of excess reactive inhibitory compounds after incubation with electrophilic chemicals or aqueous extracts of air samples derived from different sources. The inhibitory response of cigarette smoke and diesel exhaust particle extracts were compared to chemical standards of a group of electrophilic carbonyls and the arylating p-benzoquinone. GPx-1 activity was directly inactivated by millimolar concentrations of highly reactive electrophilic chemicals (including acrolein, glyoxal, methylglyoxal, and p-benzoquinone) and extracts of diesel and cigarette smoke. We conclude that the potential of air pollutant components to generate oxidative stress may be, in part, a result of electrophile-derived covalent modifications of enzymes involved in the cytosolic antioxidant defense.
登录
查看更多内容
影响因子：
10.4
作者：
通讯作者：
--
影响因子：
5.8
作者：
Kode, Aruna;Yang, Se-Ran;Rahman, Irfan
通讯作者：
Rahman, Irfan
影响因子：
4.8
作者：
Asahi, M;Fujii, J;Taniguchi, N
通讯作者：
Taniguchi, N
影响因子：
5.1
作者：
Delfino, Ralph J.;Staimer, Norbert;Vaziri, Nosratola D.
通讯作者：
Vaziri, Nosratola D.
DOI：
10.1016/j.jasms.2010.02.006
发表时间：
2010-06-01
影响因子：
3.2
作者：
Graus, Martin;Mueller, Markus;Hansel, Armin
通讯作者：
Hansel, Armin