Structure of the vacuolar H+-ATPase rotary motor reveals new mechanistic insights.
Structure
; 23(3): 461-471, 2015 Mar 03.
Article
de En
| MEDLINE
| ID: mdl-25661654
ABSTRACT
Vacuolar H(+)-ATPases are multisubunit complexes that operate with rotary mechanics and are essential for membrane proton transport throughout eukaryotes. Here we report a â¼ 1 nm resolution reconstruction of a V-ATPase in a different conformational state from that previously reported for a lower-resolution yeast model. The stator network of the V-ATPase (and by implication that of other rotary ATPases) does not change conformation in different catalytic states, and hence must be relatively rigid. We also demonstrate that a conserved bearing in the catalytic domain is electrostatic, contributing to the extraordinarily high efficiency of rotary ATPases. Analysis of the rotor axle/membrane pump interface suggests how rotary ATPases accommodate different c ring stoichiometries while maintaining high efficiency. The model provides evidence for a half channel in the proton pump, supporting theoretical models of ion translocation. Our refined model therefore provides new insights into the structure and mechanics of the V-ATPases.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Manduca
/
Protéines d'insecte
/
Vacuolar Proton-Translocating ATPases
Limites:
Animals
Langue:
En
Journal:
Structure
Sujet du journal:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
/
BIOTECNOLOGIA
Année:
2015
Type de document:
Article
Pays d'affiliation:
Royaume-Uni