Reversible Dissociation and Ligand-Glutathione Exchange Reaction in Binuclear Cationic Tetranitrosyl Iron Complex with Penicillamine
| Autor: | Alexander I. Kotelnikov, Konstantin A. Lyssenko, L. A. Syrtsova, B. L. Psikha, E. N. Kabachkov, N. I. Shkondina, Natalia A. Sanina, Sergey M. Aldoshin, Olesia Pokidova |
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| Jazyk: | angličtina |
| Rok vydání: | 2014 |
| Předmět: |
medicine.diagnostic_test
Article Subject Stereochemistry Ligand Chemistry lcsh:Biotechnology Organic Chemistry Penicillamine Cationic polymerization Glutathione Metabolism Biochemistry Medicinal chemistry Dissociation (chemistry) lcsh:QD146-197 Inorganic Chemistry Reaction rate chemistry.chemical_compound Spectrophotometry lcsh:TP248.13-248.65 medicine lcsh:Inorganic chemistry medicine.drug Research Article |
| Zdroj: | Bioinorganic Chemistry and Applications Bioinorganic Chemistry and Applications, Vol 2014 (2014) |
| ISSN: | 1565-3633 |
| DOI: | 10.1155/2014/641407 |
| Popis: | This paper describes a comparative study of the decomposition of two nitrosyl iron complexes (NICs) with penicillamine thiolic ligands [Fe2(SC5H11NO2)2(NO)4]SO4·5H2O (I) and glutathione- (GSH-) ligands [Fe2(SC10H17N3O6)2(NO)4]SO4·2H2O (II), which spontaneously evolve to NO in aqueous medium. NO formation was measured by a sensor electrode and by spectrophotometric methods by measuring the formation of a hemoglobin- (Hb-) NO complex. The NO evolution reaction rate from (I) k1= (4.6 ± 0.1)·10−3 s−1and the elimination rate constant of the penicillamine ligandk2= (1.8 ± 0.2)·10−3 s−1at 25°C in 0.05 M phosphate buffer, pH 7.0, was calculated using kinetic modeling based on the experimental data. Both reactions are reversible. Spectrophotometry and mass-spectrometry methods have firmly shown that the penicillamine ligand is exchanged for GS−during decomposition of 1.5·10−4 M (I) in the presence of 10−3 M GSH, with 76% yield in 24 h. As has been established, such behaviour is caused by the resistance of (II) to decomposition due to the higher affinity of iron to GSH in the complex. The discovered reaction may impede S-glutathionylation of the essential enzyme systems in the presence of (I) and is important for metabolism of NIC, connected with its antitumor activity. |
| Databáze: | OpenAIRE |
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