EPR spectroscopy of 5-DOXYL-stearic acid bound to the mitochondrial uncoupling protein reveals its competitive displacement by alkylsulfonates in the channel and allosteric displacement by ATP
Language English Country England, Great Britain Media print
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
7698343
DOI
10.1016/0014-5793(95)00201-j
PII: 0014-5793(95)00201-J
Knihovny.cz E-resources
- MeSH
- Allosteric Regulation MeSH
- Cyclic N-Oxides metabolism MeSH
- Electron Spin Resonance Spectroscopy MeSH
- Adipose Tissue, Brown metabolism MeSH
- Ion Channels MeSH
- Kinetics MeSH
- Binding, Competitive MeSH
- Cricetinae MeSH
- Mesocricetus MeSH
- Fatty Acids, Nonesterified pharmacology MeSH
- Sulfonic Acids pharmacology MeSH
- Membrane Proteins metabolism MeSH
- Mitochondrial Proteins MeSH
- Mitochondria metabolism MeSH
- Spin Labels MeSH
- Carrier Proteins metabolism MeSH
- Uncoupling Protein 1 MeSH
- Animals MeSH
- Check Tag
- Cricetinae MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- 5-doxylstearic acid MeSH Browser
- Cyclic N-Oxides MeSH
- Ion Channels MeSH
- Fatty Acids, Nonesterified MeSH
- Sulfonic Acids MeSH
- Membrane Proteins MeSH
- Mitochondrial Proteins MeSH
- Spin Labels MeSH
- Carrier Proteins MeSH
- Uncoupling Protein 1 MeSH
Competition of fatty acids (FA) and alkylsulfonates with 5-DOXYL-stearic acid (5-SASL) binding to isolated mitochondrial uncoupling protein (UcP) is demonstrated using EPR spectroscopy. A distinct peak of the bound 5-SASL (h+1I) decreased with increasing concentration of competitors. Since alkylsulfonates are UcP substrates, it suggests that the FA binding site is located in the anion channel. Moreover, with increasing ATP the h+1I peak decreased and was smoothed with the 'micellar' peak into a single wider peak. A pH of 8.5 reversed this effect. It could reflect an allosteric release of 5-SASL from the ATP binding site which mimics the ATP gating mechanism.
References provided by Crossref.org
Mitochondrial Uncoupling Proteins: Subtle Regulators of Cellular Redox Signaling
