Mechanical inhibition of isolated Vo from V/A-ATPase for proton conductance

Elife. 2020 Jul 8:9:e56862. doi: 10.7554/eLife.56862.

Abstract

V-ATPase is an energy converting enzyme, coupling ATP hydrolysis/synthesis in the hydrophilic V1 domain, with proton flow through the Vo membrane domain, via rotation of the central rotor complex relative to the surrounding stator apparatus. Upon dissociation from the V1 domain, the Vo domain of the eukaryotic V-ATPase can adopt a physiologically relevant auto-inhibited form in which proton conductance through the Vo domain is prevented, however the molecular mechanism of this inhibition is not fully understood. Using cryo-electron microscopy, we determined the structure of both the holo V/A-ATPase and isolated Vo at near-atomic resolution, respectively. These structures clarify how the isolated Vo domain adopts the auto-inhibited form and how the holo complex prevents formation of the inhibited Vo form.

Keywords: ATP synthase; V/A-ATPase; molecular biophysics; rotary ATPase; single particle cryo-em; structural biology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / chemistry*
  • Cryoelectron Microscopy
  • Hydrolysis
  • Protein Structure, Secondary
  • Thermus thermophilus / chemistry*
  • Thermus thermophilus / enzymology
  • Vacuolar Proton-Translocating ATPases / chemistry*

Substances

  • Bacterial Proteins
  • Vacuolar Proton-Translocating ATPases