Domain movements of plasma membrane H(+)-ATPase: 3D structures of two states by electron cryo-microscopy.
H(+)-ATPase is a P-type ATPase that transports protons across membranes using the energy from ATP hydrolysis. This hydrolysis is coupled to a conformational change between states of the protein, in which the proton-binding site is alternately accessible to the two sides of the membrane with an altered affinity. When isolated from Neurospora crassa, H(+)-ATPase is a 600 kDa hexamer of identical 100 kDa polypeptides. We have obtained the three-dimensional structures of both ligand-free and Mg(2+)/ADP-bound states of this complex using single-particle electron cryo- microscopy. Structural comparisons, together with the difference map, indicate that there is a rearrangement of the cytoplasmic domain on Mg(2+)/ADP binding, which consists of a movement of mass towards the 6-fold axis causing the structure to become more compact, accompanied by a modest conformational change in the transmembrane domain.
MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK. khrhee@mrc-lmb.cam.ac.uk
Kyong-Hi
KH
Rhee
Gene A
GA
Scarborough
Richard
R
Henderson
D000244:Adenosine Diphosphate / Q000378:metabolism; D001704:Biopolymers; D002384:Catalysis; D002462:Cell Membrane / Q000201:enzymology*; D002942:Circular Dichroism; D017136:Ion Transport; D008024:Ligands; D008274:Magnesium / Q000378:metabolism; D008854:Microscopy, Electron / Q000379:methods*; D009492:Neurospora crassa / Q000201:enzymology; D011485:Protein Binding; D011487:Protein Conformation; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000378:metabolism*; D011522:Protons; D013379:Substrate Specificity
D001704:Biopolymers; D008024:Ligands; D011522:Protons; D000244:Adenosine Diphosphate; D006180:Proton-Translocating ATPases; D008274:Magnesium