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Publication Abstract from PubMed

V-ATPases function as ATP-dependent ion pumps in various membrane systems of living organisms. ATP hydrolysis causes rotation of the central rotor complex, which is composed of the central axis D subunit and a membrane c ring that are connected by F and d subunits. Here we determined the crystal structure of the DF complex of the prokaryotic V-ATPase of Enterococcus hirae at 2.0-A resolution. The structure of the D subunit comprised a long left-handed coiled coil with a unique short beta-hairpin region that is effective in stimulating the ATPase activity of V(1)-ATPase by twofold. The F subunit is bound to the middle portion of the D subunit. The C-terminal helix of the F subunit, which was believed to function as a regulatory region by extending into the catalytic A(3)B(3) complex, contributes to tight binding to the D subunit by forming a three-helix bundle. Both D and F subunits are necessary to bind the d subunit that links to the c ring. From these findings, we modeled the entire rotor complex (DFdc ring) of V-ATPase.

Crystal structure of the central axis DF complex of the prokaryotic V-ATPase.,Saijo S, Arai S, Hossain KM, Yamato I, Suzuki K, Kakinuma Y, Ishizuka-Katsura Y, Ohsawa N, Terada T, Shirouzu M, Yokoyama S, Iwata S, Murata T Proc Natl Acad Sci U S A. 2011 Dec 13;108(50):19955-60. Epub 2011 Nov 23. PMID:22114184^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.