Temperature-dependent ESR and computational studies on antiferromagnetic electron transfer in the yeast NADH dehydrogenase Ndi1.
Phys Chem Chem Phys
; 19(6): 4849-4854, 2017 Feb 08.
Article
en En
| MEDLINE
| ID: mdl-28134365
ABSTRACT
Ndi1 is a special type-II complex I nicotinamide-adenine-dinucleotide (NADH)ubiquinone (UQ) oxidoreductase in the yeast respiratory chain, with two bound UQs (UQI and UQII) mediating electron transfer from flavin cofactors to ubiquinone, in the absence of Fe-S chains. Here, we elucidate the underlying mechanism of electron transfer in Ndi1 through temperature-dependent Electron Spin Resonance (ESR) experiments in conjunction with quantum chemical calculations. It is revealed that electron transfer is mediated by antiferromagnetic (AFM) interactions between flavin-adenosine-dinucleotide (FAD) and UQI and between UQI and UQII. The π-stacking interactions among the aromatic complexes also enhance the through-space electron transfer. The FAD/UQI pair works as a rectifier converting double-electron co-transfer into sequential single-electron transfer events. The results not only expand our understanding on the observed AFM interactions among p-orbital aromatic mixed-stack in proteins, but also provide significant insights into the fabrication of materials with special magnetic properties using biological samples.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Temperatura
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Espectroscopía de Resonancia por Spin del Electrón
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Proteínas de Saccharomyces cerevisiae
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Complejo I de Transporte de Electrón
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Transporte de Electrón
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Modelos Químicos
Idioma:
En
Revista:
Phys Chem Chem Phys
Asunto de la revista:
BIOFISICA
/
QUIMICA
Año:
2017
Tipo del documento:
Article