P14 Volker Müller
ATP synthases are key elements in cellular bioenergetics. They developed very early in evolution but still little is known about ATP synthases from life forms such as archaea or bacteria that have an ancient life style. Our own preparatory work revealed unique ATP synthases with unprecedented subunit composition, unique biochemical features and ion-binding sites in archaea and the acetogenic bacterium Acetobacterium woodii that have evolved to allow growth under extreme energy limitation. The heterologous and homologous expression systems that we have set up enables us to address the structure/function relationship of these unique enzymes by mutational analyses followed by biochemical, bioenergetic and biophysical studies. In particular we will focus on the structure of the entire archaeal A1AO ATP synthase and its subcomplexes, the number of c subunits and ion-binding sites in the motor and the evolution of the ion-binding site from Na+ over Na+ + H+ to H+ in the membrane-embedded motor. For the Na+ F1FO ATP synthase of A. woodii, we will unravel the structure of the unique FOVO hybrid rotor, the role of the different rotor subunits in ion transport and rotor assembly, the rotor dynamics and explore the evolutionary advantage of the FOVO hybrid rotor with its decreased Na+/ATP stoichiometry.
High-resolution AFM topographs (A-C) and electron micrographs (D) of reconstituted c rings from Acebacterium woodii. Each ring is either neighbored by rings either exposing their wide or narrow ends. Reference free correlation averages of the different assemblies revealed 11 masses forming wide and narrow end of the rings. (D) shows a projection map of 13 merged images at 5 Å resolution. One unit cell of plane group p22,2, with its symmetry elements (two-fold rotation axes and screw axes) is indicated. The unit cell measures 100.3 x 108 Å and contains four c rings.
Structural model of the A1Ao ATP synthase from Pyrococcus furiosus based on single particle analyses. X-ray structures of subunits from F- or A-ATP synthases were fitted into the map. The a subunit is given in yellow, the two peripheral stalks are made by EH-dimers (pink), and the size of the Ao domain is sufficient to harbour the 16-hairpin c-ring from Enterococcus hirae.
Brandt K, Müller D, Hoffmann J, Langer J, Brutschy B, Morgner N, Müller V (2015) Stoichiometry and deletion analyses of subunits in the heterotrimeric F-ATP synthase c-ring from the acetogenic bacterium Acetobacterium woodii. FEBS J 283, 510-520.
Spahn S, Brandt K, Müller V (2015) A low phosphorylation potential in the acetogen Acetobacterium woodii reflects its lifestyle at the thermodynamic edge of life. Arch Microbiol 197, 745-751.
Gloger C, Born AK, Antosch M, Müller V (2015) The a subunit of the A1AO ATP synthase of Methanosarcina mazei Gö1 contains two conserved arginine residues that are crucial for ATP synthesis. Biochim Biophys Acta – Bioenergetics 1847, 505-13.
Mayer F, Lim JK, Langer JD, Kang SG, Müller V (2015) Na+ transport by the A1AO ATP synthase purified from Thermococcus onnurineus and reconstituted into liposomes. J Biol Chem 290, 6994-7002.
Matthies D, Zhou W, Klyszejko A, Anselmi C, Yildiz Ö, Brandt K, Müller V, Faraldo-Gómez JD, Meier T (2014) High-resolution structure and mechanism of an F/V-hybrid rotor ring in a Na+-coupled ATP synthase. Nat Commun 5, 5286.
Lim JK, Mayer F, Kang SG, Müller V (2014) Energy conservation by oxidation of formate to carbon dioxide and hydrogen via sodium ion current in a hyperthermophilic archaeon. Proc Natl Acad Sci USA 111, 11497-502.
Grüber G, Manimekalai MSS, Mayer F, Müller V (2014) ATP synthases from archaea: The beauty of a molecular motor. Biochim Biophys Acta - Bioenergetics 1837, 940-52.
Mayer F, Müller V (2013) Adaptations of anaerobic archaea to life under extreme energy limitation. FEMS Microbiol Rev 38, 449-72.
Brandt K, Müller DB, Hoffmann J, Hübert C, Brutschy B, Deckers-Hebestreit G, Müller V (2013) Functional production of the Na+ F1FO ATP synthase from Acetobacterium woodii in Escherichia coli requires the native AtpI. J Bioenerg Biomembr 45, 15-23.
Mayer F, Leone V, Langer JD, Faraldo-Gómez JD, Müller V (2012) A c subunit with four transmembrane helices and one ion (Na+) binding site in an archaeal ATP synthase: Implications for c ring function and structure. J Biol Chem 287, 39327-37.
Schlegel K, Leone V, Faraldo-Gómez JD, Müller V (2012) Promiscuous archaeal ATP synthase concurrently coupled to Na+ and H+ translocation. Proc Natl Acad Sci USA 109, 947-952.