V-ATPase
From Proteopedia
Contents |
Introduction
Vacuolar (H+)-ATPases (V-ATPases)[1] are mainly found in vacuoles of eukaryotic cells where they catalyze the hydrolysis of ATP in order to transport solutes. V-ATPases are structurally and mechanically related to F- and A-ATPases.[2]
V-ATPase components
The structure of the whole V-ATPase complex can be divided in two domains. The V1 domain, which consist of eight different sub-units (A-H) and is responsible for the hydrolysis of ATP, and the intermembrane V0 domain consisting of six different sub-units (a, d, e, c, c' and c") and which acts as a proton translocator from the cytoplasm to the lumen.[3]
ATP hydrolysis occurs at catalytic sites located at the interface of the A and B subunits.
V1-domain
|
V0-domain
Mechanism of rotation
3D V-ATPase structures
See ATPase
EMDB
5335: 9.7Å resolution map of Thermus Thermophilus V-ATPase.
1888: 16Å resolution map of Thermus Thermophilus V-ATPase.
1640: 25Å resolution map of Saccharomyces cerevisiae V-ATPase.
1590: 17Å resolution map of Manduca sexta V-ATPase.
References
- ↑ Forgac M. Vacuolar ATPases: rotary proton pumps in physiology and pathophysiology. Nat Rev Mol Cell Biol. 2007 Nov;8(11):917-29. PMID:17912264 doi:10.1038/nrm2272
- ↑ Cross RL, Muller V. The evolution of A-, F-, and V-type ATP synthases and ATPases: reversals in function and changes in the H+/ATP coupling ratio. FEBS Lett. 2004 Oct 8;576(1-2):1-4. PMID:15473999 doi:10.1016/j.febslet.2004.08.065
- ↑ Toei M, Saum R, Forgac M. Regulation and isoform function of the V-ATPases. Biochemistry. 2010 Jun 15;49(23):4715-23. PMID:20450191 doi:10.1021/bi100397s