28542-76-9Relevant articles and documents
Glutathione-complexed iron-sulfur clusters. Reaction intermediates and evidence for a template effect promoting assembly and stability
Qi, Wenbin,Li, Jingwei,Chain,Pasquevich,Pasquevich,Cowan
, p. 6313 - 6315 (2013)
Assembly and stabilization of a glutathione-complexed [2Fe-2S] cluster is promoted by aggregation of glutathione. The cluster core selects the tetramer species from a collection of equilibrating solution aggregate species, and in turn the core is stabilized toward hydrolytic degradation. Studies of glutathione derivatives, in combination with mass spectrometric and Moessbauer investigations provide insight on reaction intermediates during formation of [2Fe-2S](GS)42-.
Glutathione-complexed iron-sulfur clusters. Reaction intermediates and evidence for a template effect promoting assembly and stability
Qi, Wenbin,Li, Jingwei,Chain,Pasquevich,Pasquevich,Cowan
supporting information, p. 6313 - 6315 (2013/08/23)
Assembly and stabilization of a glutathione-complexed [2Fe-2S] cluster is promoted by aggregation of glutathione. The cluster core selects the tetramer species from a collection of equilibrating solution aggregate species, and in turn the core is stabilized toward hydrolytic degradation. Studies of glutathione derivatives, in combination with mass spectrometric and Moessbauer investigations provide insight on reaction intermediates during formation of [2Fe-2S](GS)42-.
Ring addition of the α-amino group of glutathione increases the reactivity of benzoquinone thioethers
Alt, Carmen,Eyer, Peter
, p. 1223 - 1233 (2007/10/03)
2-(Glutathion-S-yl)-1,4-benzoquinone was found to be remarkably unstable in phosphate butter (pH 7.4) even in the absence of oxygen. Intramolecular addition of the α-amino group of the glutamate residue to the quinone ring yielded ultimately 2,3-(glutathion-N,S-yl)-1,4-benzoquinone and 2,6- (glutathion-N,S-yl)-1,4-benzoquinone in a 3:1 ratio along with 2-(glutathion- S-yl)-1,4-hydroquinone. Kinetic studies indicated that the cyclization reactions proceeded at a rate k1 of 0.093 min-1, while intermolecular reactions followed a second-order kinetics with a k2 of 94 M-1 min-1 (pH 7.4, 37 °C), resulting in multiple polymerization products. Both intramolecular amino adducts of 2-(glutathion-S-yl)-1;4-benzoquinone are prone to hydrolysis, leading to the insertion of an additional OH group in the ring. These S-substituted trihydroxybenzene derivatives are particularly susceptible to autoxidation. The model compound 6-(N-acetylcystein-S-yl)-2- hydroxy-1,4-hydroquinone was shown to form readily two atropoisomeric biphenyls upon autoxidation: 2,4'-bis(N-acetylcystein-S-yl)-2',3,3',4,6,6'- hexahydroxybiphenyl, indicating C-C coupling, presumably via semiquinone radical intermediates. Thus, the sequence of glutathione S-addition, followed by oxidation, N-addition, oxidation, an 1 hydrolysis, constitutes a novel and very effective activation pathway of quinones for eliciting oxidative stress. These data underline the fact that glutathione conjugates of autoxidizable aromatics are no obligatory stable end products of a detoxication reaction. The possible toxicological impacts of intra- and intermolecular addition reactions of quinoid thiol conjugates are discussed.
