Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and Selenocysteamine
Microscopic redox equilibrium constants and standard redox potential values were determined to quantify selenolate-diselenide equilibria of biological significance. The highly composite, codependent acid-base and redox equilibria of selenolates could so far be converted into pH-dependent, apparent p...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-06-01
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| Series: | Antioxidants |
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| Online Access: | https://www.mdpi.com/2076-3921/9/6/465 |
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| author | Tamás Pálla Arash Mirzahosseini Béla Noszál |
| author_facet | Tamás Pálla Arash Mirzahosseini Béla Noszál |
| author_sort | Tamás Pálla |
| collection | DOAJ |
| description | Microscopic redox equilibrium constants and standard redox potential values were determined to quantify selenolate-diselenide equilibria of biological significance. The highly composite, codependent acid-base and redox equilibria of selenolates could so far be converted into pH-dependent, apparent parameters (equilibrium constants, redox potentials) only. In this work, the selenolate-diselenide redox equilibria of selenocysteamine and selenocysteine against dithiothreitol were analyzed by quantitative nuclear magnetic resonance (NMR) methods to characterize the interfering acid-base and redox equilibria. The directly obtained, pH-dependent, conditional redox equilibrium constants were then decomposed by our method into pH-independent, microscopic constants, which characterize the two-electron redox transitions of selenocysteamine and selenocysteine. The 12 different, species-specific parameter values show close correlation with the respective selenolate basicities, providing a tool to estimate otherwise inaccessible site-specific selenolate-diselenide redox potentials of related moieties in large peptides and proteins. |
| first_indexed | 2024-03-10T19:28:14Z |
| format | Article |
| id | doaj.art-eac07b9da700406d9171ab18dbd844bc |
| institution | Directory Open Access Journal |
| issn | 2076-3921 |
| language | English |
| last_indexed | 2024-03-10T19:28:14Z |
| publishDate | 2020-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Antioxidants |
| spelling | doaj.art-eac07b9da700406d9171ab18dbd844bc2023-11-20T02:27:00ZengMDPI AGAntioxidants2076-39212020-06-019646510.3390/antiox9060465Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and SelenocysteamineTamás Pálla0Arash Mirzahosseini1Béla Noszál2Department of Pharmaceutical Chemistry, Semmelweis University, H-1092 Budapest, HungaryDepartment of Pharmaceutical Chemistry, Semmelweis University, H-1092 Budapest, HungaryDepartment of Pharmaceutical Chemistry, Semmelweis University, H-1092 Budapest, HungaryMicroscopic redox equilibrium constants and standard redox potential values were determined to quantify selenolate-diselenide equilibria of biological significance. The highly composite, codependent acid-base and redox equilibria of selenolates could so far be converted into pH-dependent, apparent parameters (equilibrium constants, redox potentials) only. In this work, the selenolate-diselenide redox equilibria of selenocysteamine and selenocysteine against dithiothreitol were analyzed by quantitative nuclear magnetic resonance (NMR) methods to characterize the interfering acid-base and redox equilibria. The directly obtained, pH-dependent, conditional redox equilibrium constants were then decomposed by our method into pH-independent, microscopic constants, which characterize the two-electron redox transitions of selenocysteamine and selenocysteine. The 12 different, species-specific parameter values show close correlation with the respective selenolate basicities, providing a tool to estimate otherwise inaccessible site-specific selenolate-diselenide redox potentials of related moieties in large peptides and proteins.https://www.mdpi.com/2076-3921/9/6/465selenocysteineredoxdisulfide |
| spellingShingle | Tamás Pálla Arash Mirzahosseini Béla Noszál Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and Selenocysteamine Antioxidants selenocysteine redox disulfide |
| title | Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and Selenocysteamine |
| title_full | Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and Selenocysteamine |
| title_fullStr | Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and Selenocysteamine |
| title_full_unstemmed | Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and Selenocysteamine |
| title_short | Species-Specific, pH-Independent, Standard Redox Potential of Selenocysteine and Selenocysteamine |
| title_sort | species specific ph independent standard redox potential of selenocysteine and selenocysteamine |
| topic | selenocysteine redox disulfide |
| url | https://www.mdpi.com/2076-3921/9/6/465 |
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