The mechanochemistry of V-ATPase proton pumps.
The vacuolar H(+)-ATPases (V-ATPases) are a universal class of proton pumps that are structurally similar to the F-ATPases. Both protein families are characterized by a membrane-bound segment (V(o), F(o)) responsible for the translocation of protons, and a soluble portion, (V(1), F(1)), which supplies the energy for translocation by hydrolyzing ATP. Here we present a mechanochemical model for the functioning of the V(o) ion pump that is consistent with the known structural features and biochemistry. The model reproduces a variety of experimental measurements of performance and provides a unified view of the many mechanisms of intracellular pH regulation.
Grabe
M
M
Departments of Physics, University of California, Berkeley 94720-3112, USA.
Wang
H
H
Oster
G
G
D000255:Adenosine Triphosphate / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology / Q000648:ultrastructure; D006863:Hydrogen-Ion Concentration; D046911:Macromolecular Substances; D008564:Membrane Potentials; D008958:Models, Molecular; D008962:Models, Theoretical; D009492:Neurospora crassa / Q000201:enzymology; D011487:Protein Conformation; D006180:Proton-Translocating ATPases / Q000737:chemistry* / Q000378:metabolism*; D019415:Torque; D025262:Vacuolar Proton-Translocating ATPases
D046911:Macromolecular Substances; D000255:Adenosine Triphosphate; D025262:Vacuolar Proton-Translocating ATPases; D006180:Proton-Translocating ATPases