The proton-translocating a subunit of F0F1-ATP synthase is allocated asymmetrically to the peripheral stalk.
J Biol Chem
; 283(48): 33602-10, 2008 Nov 28.
Article
en En
| MEDLINE
| ID: mdl-18786919
The position of the a subunit of the membrane-integral F0 sector of Escherichia coli ATP synthase was investigated by single molecule fluorescence resonance energy transfer studies utilizing a fusion of enhanced green fluorescent protein to the C terminus of the a subunit and fluorescent labels attached to specific positions of the epsilon or gamma subunits. Three fluorescence resonance energy transfer levels were observed during rotation driven by ATP hydrolysis corresponding to the three resting positions of the rotor subunits, gamma or epsilon, relative to the a subunit of the stator. Comparison of these positions of the rotor sites with those previously determined relative to the b subunit dimer indicates the position of a as adjacent to the b dimer on its counterclockwise side when the enzyme is viewed from the cytoplasm. This relationship provides stability to the membrane interface between a and b2, allowing it to withstand the torque imparted by the rotor during ATP synthesis as well as ATP hydrolysis.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Modelos Moleculares
/
Subunidades de Proteína
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ATPasas de Translocación de Protón Bacterianas
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Proteínas de Escherichia coli
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Escherichia coli
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Complejos Multienzimáticos
Idioma:
En
Revista:
J Biol Chem
Año:
2008
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Estados Unidos