Structure of the F1-binding domain of the stator of bovine F1Fo-ATPase and how it binds an alpha-subunit.

TitleStructure of the F1-binding domain of the stator of bovine F1Fo-ATPase and how it binds an alpha-subunit.
Publication TypeJournal Article
Year of Publication2005
AuthorsCarbajo, RJ, Kellas, FA, Runswick, MJ, Montgomery, MG, Walker, JE, Neuhaus, D
JournalJ Mol Biol
Volume351
Issue4
Pagination824-38
Date Published2005 Aug 26
ISSN0022-2836
KeywordsAdenosine Triphosphatases, Amino Acid Sequence, Animals, Binding Sites, Carrier Proteins, Cattle, In Vitro Techniques, Membrane Proteins, Mitochondrial Proton-Translocating ATPases, Models, Molecular, Molecular Sequence Data, Nuclear Magnetic Resonance, Biomolecular, Peptide Fragments, Protein Structure, Tertiary, Protein Subunits, Recombinant Proteins, Sequence Homology, Amino Acid, Static Electricity
Abstract

The peripheral stalk of ATP synthase holds the alpha3beta3 catalytic subcomplex stationary against the torque of the rotating central stalk. In bovine mitochondria, the N-terminal domain of the oligomycin sensitivity conferral protein (OSCP-NT; residues 1-120) anchors one end of the peripheral stalk to the N-terminal tails of one or more alpha-subunits of the F1 subcomplex. Here we present the solution structure of OSCP-NT and an NMR titration study of its interaction with peptides representing N-terminal tails of F1 alpha-subunits. The structure comprises a bundle of six alpha-helices, and its interaction site contains adjoining hydrophobic surfaces of helices 1 and 5; residues in the region 1-8 of the alpha-subunit are essential for the interaction. The OSCP-NT is similar to the N-terminal domain of the delta-subunit from Escherichia coli ATP synthase (delta-NT), except that their surface charges differ (basic and acidic, respectively). As the charges of the adjacent crown regions in their alpha3beta3 complexes are similar, the OSCP-NT and delta-NT probably do not contact the crowns extensively. The N-terminal tails of alpha-subunit tails are probably alpha-helical, and so this interface, which is essential for the rotary mechanism of the enzyme, appears to consist of helix-helix interactions.

DOI10.1016/j.jmb.2005.06.012
Alternate JournalJ. Mol. Biol.
Citation Key10.1016/j.jmb.2005.06.012
PubMed ID16045926