6533b834fe1ef96bd129cd36
RESEARCH PRODUCT
New evidence for the multiplicity of ubiquinone- and inhibitor-binding sites in the mitochondrial complex I.
Ernesto EstornellJosé R. Tormosubject
BioenergeticsStereochemistryUbiquinoneSubmitochondrial ParticlesBiophysicsBiologyIn Vitro TechniquesBiochemistryModels BiologicalMitochondria HeartSubstrate SpecificityOxidoreductaseAnimalsNADH NADPH OxidoreductasesBinding siteMultiplicity (chemistry)Molecular Biologychemistry.chemical_classificationNADH-Ubiquinone OxidoreductaseBinding SitesElectron Transport Complex IKineticsEnzymechemistryBiochemistryCattleEnergy MetabolismMitochondrial Complex Idescription
Determination of the number of ubiquinone- and inhibitor-binding sites in the mitochondrial complex I (NADH:ubiquinone oxidoreductase) is a controversial question with a direct implication for elaborating a suitable model to explain the bioenergetic mechanism of this complicated enzyme. We have used combinations of both selective inhibitors and common ubiquinone-like substrates to demonstrate the multiplicity of the reaction centers in the complex I in contrast with competition studies that have suggested the existence of a unique binding site for ubiquinone. Our results provide new evidence for the existence of at least two freely exchangeable ubiquinone-binding sites with different specificity for substrates, as well as for a different kinetic interaction of inhibitors with the enzyme.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2000-10-14 | Archives of biochemistry and biophysics |