Structural basis of redox modulation on chloroplast ATP synthase.
Commun Biol
; 3(1): 482, 2020 09 02.
Article
em En
| MEDLINE
| ID: mdl-32879423
ABSTRACT
In higher plants, chloroplast ATP synthase has a unique redox switch on its γ subunit that modulates enzyme activity to limit ATP hydrolysis at night. To understand the molecular details of the redox modulation, we used single-particle cryo-EM to determine the structures of spinach chloroplast ATP synthase in both reduced and oxidized states. The disulfide linkage of the oxidized γ subunit introduces a torsional constraint to stabilize the two ß hairpin structures. Once reduced, free cysteines alleviate this constraint, resulting in a concerted motion of the enzyme complex and a smooth transition between rotary states to facilitate the ATP synthesis. We added an uncompetitive inhibitor, tentoxin, in the reduced sample to limit the flexibility of the enzyme and obtained high-resolution details. Our cryo-EM structures provide mechanistic insight into the redox modulation of the energy regulation activity of chloroplast ATP synthase.
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Spinacia oleracea
/
ATPases de Cloroplastos Translocadoras de Prótons
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Commun Biol
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Estados Unidos