Iron catalyzes both decomposition and synthesis of S-nitrosothiols: optical and electron paramagnetic resonance studies.
Iron catalyzes both decomposition and synthesis of S-nitrosothiols: optical and electron paramagnetic resonance studies.
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铁催化 S-亚硝基硫醇的分解和合成：光学和电子顺磁共振研究。
DOI：
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
V. Serezhenkov
中科院分区：
文献类型：
--
作者：
A. Vanin;I. V. Malenkova;V. Serezhenkov
在1-50 mm半胱氨酸或谷胱甘肽(分别为Cys-NO和GS-NO)的水溶液中，硫醇在50-600 mm的压力下与气态一氧化氮接触，在厌氧条件下生成S-亚硝硫醇。以摩尔比[NO]/[O2 from Air]不低于40的摩尔比[NO]/[O2(空气中的O2)]与NO加空气混合，可提高S亚硫醇的产率。在这种情况下，在100-150毫米汞柱的NO压力下，S-亚硫醇的生成是最佳的。在不加或不加空气的硫醇溶液中加入选择性Fe2+螯合剂邻菲咯啉0.25mM，可完全阻断S亚硫醇的生成。另一方面，Fe2+的加入增强了这一过程，而Cu2+的加入没有增强这一过程。这些数据表明，Fe2+对这一过程有重要影响。邻菲咯啉与常规方法合成的S-亚硝硫醇(用pH=1的NO+NO2混合物处理硫醇溶液)在pH 3~10范围内不发生降解反应。在中性pH条件下，邻菲咯啉显著提高了Cys-NO的稳定性。半胱氨酸、谷胱甘肽和选择性Fe3+螯合剂Desferal对Cys-NO也有类似的影响。硫醇对Cys-NO的稳定作用伴随着二亚硝基铁络合物与含硫醇配体的混合(本征)铁(1-2微米)的形成。当Fe2+浓度高于10微米时，硫醇对Cys-NO的稳定作用消失。因此，铁既能诱导S亚硫醇的降解，又能诱导其合成。根据所提出的机理，铁对S-亚硫醇的这种相反作用是由反应体系中S-亚硝硫醇、硫醇、铁和NO之间的比例决定的。
Formation of S-nitrosothiols was demonstrated in 1-50 mM aqueous solutions of cysteine or glutathione (cys-NO or GS-NO, respectively) upon contact of thiols with gaseous nitric oxide under a pressure of 50-600 mm Hg and anaerobic conditions. The yield of S-nitrosothiols was increased by mixing with NO plus air at a molar ratio [NO]/[O2 from air] of no less than 40. In this instance, the S-nitrosothiol formation was optimum at a NO pressure of 100-150 mm Hg. The addition of 0.25 mM o-phenanthroline, a selective Fe2+ chelator, to thiol solutions prior to the treatment with NO or NO + air completely blocked the formation of S-nitrosothiols. On the other hand, this process was potentiated by the addition of Fe2+ but not Cu2+ ions. These data indicated a crucial influence of Fe2+ on the process. The contact of o-phenanthroline with S-nitrosothiols synthesized by a routine method (treatment of thiol solutions with the NO + NO2 mixture at pH <1) did not induce their degradation at pH 3-10. Moreover, o-phenanthroline strikingly enhanced the cys-NO stability at neutral pH. Cysteine, glutathione, and desferal, a selective Fe3+ chelator, exerted a similar effect on cys-NO. The stabilizing effect of thiols on cys-NO was accompanied by the formation of dinitrosyl-iron complexes with thiol-containing ligands containing admixed (intrinsic) iron (1-2 microM). The addition of Fe2+ at a concentration higher than 10 microM abolished the stabilizing effect of thiols on cys-NO. Therefore iron can induce both degradation and synthesis of S-nitrosothiols. According to the proposed mechanisms such opposite effects of iron on S-nitrosothiols are determined by the ratio between S-nitrosothiols, thiols, iron, and NO in the reaction system.
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影响因子：
3.9
作者：
ARNELLE, DR;STAMLER, JS
通讯作者：
STAMLER, JS
DOI：
10.1073/pnas.89.16.7674
发表时间：
1992-08-15
影响因子：
11.1
作者：
STAMLER, JS;JARAKI, O;LOSCALZO, J
通讯作者：
LOSCALZO, J
影响因子：
56.9
作者：
STAMLER, JS;SINGEL, DJ;LOSCALZO, J
通讯作者：
LOSCALZO, J
DOI：
10.1073/pnas.89.1.444
发表时间：
1992-01-01
影响因子：
11.1
作者：
STAMLER, JS;SIMON, DI;LOSCALZO, J
通讯作者：
LOSCALZO, J