title: Low resolution structure of subunit b (b (22-156)) of Escherichia coli F(1)F(O) ATP synthase in solution and the b-delta assembly.
abstract: The first low resolution solution structure of the soluble domain of subunit b (b (22-156)) of the Escherichia coli F(1)F(O) ATPsynthase was determined from small-angle X-ray scattering data. The dimeric protein has a boomerang-like shape with a total length of 16.2 +/- 0.3 nm. Fluorescence correlation spectroscopy (FCS) shows that the protein binds effectively to the subunit delta, confirming their described neighborhood. Using the recombinant C-terminal domain (delta(91-177)) of subunit delta and the C-terminal peptides of subunit b, b (120-140) and b (140-156), FCS titration experiments were performed to assign the segments involved in delta-b assembly. These data identify the very C-terminal tail b (140-156) to interact with delta(91-177). The novel 3D structure of this peptide has been determined by NMR spectroscopy. The molecule adopts a stable helix formation in solution with a flexible tail between amino acid 140 to 145.
authors.affiliation: School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
authors.forename: Ragunathan
authors.initials: R
authors.lastname: Priya
authors.forename: Vikeramjeet S
authors.initials: VS
authors.lastname: Tadwal
authors.forename: Manfred W
authors.initials: MW
authors.lastname: Roessle
authors.forename: Shovanlal
authors.initials: S
authors.lastname: Gayen
authors.forename: Cornelia
authors.initials: C
authors.lastname: Hunke
authors.forename: Weng Chuan
authors.initials: WC
authors.lastname: Peng
authors.forename: Jaume
authors.initials: J
authors.lastname: Torres
authors.forename: Gerhard
authors.initials: G
authors.lastname: Grüber
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry*; D025243:Bacterial Proton-Translocating ATPases / Q000737:chemistry* / Q000648:ultrastructure*; D001665:Binding Sites; D003198:Computer Simulation; D004789:Enzyme Activation; D004795:Enzyme Stability; D004926:Escherichia coli / Q000201:enzymology*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D021122:Protein Subunits / Q000737:chemistry
chemical_list: D021122:Protein Subunits; D000255:Adenosine Triphosphate; D025243:Bacterial Proton-Translocating ATPases