Electric Field-Driven ATP Synthesis Catalyzed by the Membrane-Bound ATP-Synthase from Chloroplasts

1988 ◽  
Vol 92 (9) ◽  
pp. 1036-1039 ◽  
Author(s):  
Hans Bauermeister ◽  
Eberhard Schlodder ◽  
Peter Gräber
Keyword(s):  
Electric Field ◽  
Atp Synthase ◽  
Atp Synthesis ◽  
Membrane Bound

scholarly journals Energy Conservation by the H2:Heterodisulfide Oxidoreductase from Methanosarcina mazei Gö1: Identification of Two Proton-Translocating Segments

1999 ◽  
Vol 181 (13) ◽  
pp. 4076-4080 ◽  
Author(s):  
Tina Ide ◽  
Sebastian Bäumer ◽  
Uwe Deppenmeier
Keyword(s):  
Electron Transport ◽  
Atp Synthase ◽  
Cytoplasmic Membrane ◽  
Respiratory Control ◽  
Atp Synthesis ◽  
Heterodisulfide Reductase ◽  
Methanosarcina Mazei ◽  
Energy Conserving ◽  
Membrane Bound ◽  
Synthase Inhibitor

ABSTRACT The membrane-bound H2:heterodisulfide oxidoreductase system of the methanogenic archaeon Methanosarcina mazeiGö1 catalyzed the H2-dependent reduction of 2-hydroxyphenazine and the dihydro-2-hydroxyphenazine-dependent reduction of the heterodisulfide of HS-CoM and HS-CoB (CoM-S-S-CoB). Washed inverted vesicles of this organism were found to couple both processes with the transfer of protons across the cytoplasmic membrane. The maximal H+/2e− ratio was 0.9 for each reaction. The electrochemical proton gradient (ΔμH+ ) thereby generated was shown to drive ATP synthesis from ADP plus Pi, exhibiting stoichiometries of 0.25 ATP synthesized per two electrons transported for both partial reactions. ATP synthesis and the generation of ΔμH+ were abolished by the uncoupler 3,5-di-tert-butyl-4-hydroxybenzylidenemalononitrile (SF 6847). The ATP synthase inhibitorN,N′-dicyclohexylcarbodiimide did not affect H+ translocation but led to an almost complete inhibition of ATP synthesis and decreased the electron transport rates. The latter effect was relieved by the addition of SF 6847. Thus, the energy-conserving systems showed a stringent coupling which resembles the phenomenon of respiratory control. The results indicate that two different proton-translocating segments are present in the H2:heterodisulfide oxidoreductase system; the first involves the 2-hydroxyphenazine-dependent hydrogenase, and the second involves the heterodisulfide reductase.

External electric field driven ATP synthesis in chloroplasts: a slow, ATP synthase-dependent reaction

FEBS Letters ◽  
1982 ◽  
Vol 145 (2) ◽  
pp. 235-240 ◽  
Author(s):  
Chana Vinkler ◽  
Rafi Korenstein ◽  
Daniel L. Farkas
Keyword(s):  
Electric Field ◽  
External Electric Field ◽  
Atp Synthase ◽  
Atp Synthesis

scholarly journals Biochemical and Molecular Characterization of a Na+-Translocating F1Fo-ATPase from the Thermoalkaliphilic Bacterium Clostridium paradoxum

2006 ◽  
Vol 188 (14) ◽  
pp. 5045-5054 ◽  
Author(s):  
Scott A. Ferguson ◽  
Stefanie Keis ◽  
Gregory M. Cook
Keyword(s):  
Atp Synthase ◽  
Electrical Potential ◽  
Atp Synthesis ◽  
Membrane Vesicles ◽  
Binding Motif ◽  
Sodium Ions ◽  
Membrane Bound ◽  
Transmembrane Electrical Potential ◽  
Synthase Inhibitor

ABSTRACT Clostridium paradoxum is an anaerobic thermoalkaliphilic bacterium that grows rapidly at pH 9.8 and 56°C. Under these conditions, growth is sensitive to the F-type ATP synthase inhibitor N,N′-dicyclohexylcarbodiimide (DCCD), suggesting an important role for this enzyme in the physiology of C. paradoxum. The ATP synthase was characterized at the biochemical and molecular levels. The purified enzyme (30-fold purification) displayed the typical subunit pattern for an F1Fo-ATP synthase but also included the presence of a stable oligomeric c-ring that could be dissociated by trichloroacetic acid treatment into its monomeric c subunits. The purified ATPase was stimulated by sodium ions, and sodium provided protection against inhibition by DCCD that was pH dependent. ATP synthesis in inverted membrane vesicles was driven by an artificially imposed chemical gradient of sodium ions in the presence of a transmembrane electrical potential that was sensitive to monensin. Cloning and sequencing of the atp operon revealed the presence of a sodium-binding motif in the membrane-bound c subunit (viz., Q28, E61, and S62). On the basis of these properties, the F1Fo-ATP synthase of C. paradoxum is a sodium-translocating ATPase that is used to generate an electrochemical gradient of Na+ that could be used to drive other membrane-bound bioenergetic processes (e.g., solute transport or flagellar rotation). In support of this proposal are the low rates of ATP synthesis catalyzed by the enzyme and the lack of the C-terminal region of the ε subunit that has been shown to be essential for coupled ATP synthesis.

scholarly journals Assembly of the membrane domain of ATP synthase in human mitochondria

2018 ◽  
Vol 115 (12) ◽  
pp. 2988-2993 ◽  
Author(s):  
Jiuya He ◽  
Holly C. Ford ◽  
Joe Carroll ◽  
Corsten Douglas ◽  
Evvia Gonzales ◽  
...  
Keyword(s):  
Atp Synthase ◽  
Atp Synthesis ◽  
Membrane Domain ◽  
Atpase Inhibitor ◽  
Peripheral Stalk ◽  
Mitochondrial Ribosomes ◽  
Human Genes ◽  
The Matrix ◽  
Membrane Bound ◽  
Membrane Components

The ATP synthase in human mitochondria is a membrane-bound assembly of 29 proteins of 18 kinds. All but two membrane components are encoded in nuclear genes, synthesized on cytoplasmic ribosomes, and imported into the matrix of the organelle, where they are assembled into the complex with ATP6 and ATP8, the products of overlapping genes in mitochondrial DNA. Disruption of individual human genes for the nuclear-encoded subunits in the membrane portion of the enzyme leads to the formation of intermediate vestigial ATPase complexes that provide a description of the pathway of assembly of the membrane domain. The key intermediate complex consists of the F1-c8 complex inhibited by the ATPase inhibitor protein IF1 and attached to the peripheral stalk, with subunits e, f, and g associated with the membrane domain of the peripheral stalk. This intermediate provides the template for insertion of ATP6 and ATP8, which are synthesized on mitochondrial ribosomes. Their association with the complex is stabilized by addition of the 6.8 proteolipid, and the complex is coupled to ATP synthesis at this point. A structure of the dimeric yeast Fo membrane domain is consistent with this model of assembly. The human 6.8 proteolipid (yeast j subunit) locks ATP6 and ATP8 into the membrane assembly, and the monomeric complexes then dimerize via interactions between ATP6 subunits and between 6.8 proteolipids (j subunits). The dimers are linked together back-to-face by DAPIT (diabetes-associated protein in insulin-sensitive tissue; yeast subunit k), forming long oligomers along the edges of the cristae.

scholarly journals Rates of various reactions catalyzed by ATP synthase as related to the mechanism of ATP synthesis.

1991 ◽  
Vol 266 (1) ◽  
pp. 123-129
Author(s):  
D A Berkich ◽  
G D Williams ◽  
P T Masiakos ◽  
M B Smith ◽  
P D Boyer ◽  
...  
Keyword(s):  
Atp Synthase ◽  
Atp Synthesis

scholarly journals Carbon and Nitrogen Sources Have No Impact on the Organization and Composition of Ustilago maydis Respiratory Supercomplexes

2021 ◽  
Vol 7 (1) ◽  
pp. 42
Author(s):  
Deyamira Matuz-Mares ◽  
Oscar Flores-Herrera ◽  
Guadalupe Guerra-Sánchez ◽  
Lucero Romero-Aguilar ◽  
Héctor Vázquez-Meza ◽  
...  
Keyword(s):  
Atp Synthase ◽  
Polyacrylamide Gel Electrophoresis ◽  
Atp Synthesis ◽  
Nitrogen Sources ◽  
Growth Conditions ◽  
Energy Conditions ◽  
Respiratory Complexes ◽  
Respiratory Supercomplexes ◽  
Nadh Dehydrogenases ◽  
Reduced Nicotinamide Adenine Dinucleotide

Respiratory supercomplexes are found in mitochondria of eukaryotic cells and some bacteria. A hypothetical role of these supercomplexes is electron channeling, which in principle should increase the respiratory chain efficiency and ATP synthesis. In addition to the four classic respiratory complexes and the ATP synthase, U. maydis mitochondria contain three type II NADH dehydrogenases (NADH for reduced nicotinamide adenine dinucleotide) and the alternative oxidase. Changes in the composition of the respiratory supercomplexes due to energy requirements have been reported in certain organisms. In this study, we addressed the organization of the mitochondrial respiratory complexes in U. maydis under diverse energy conditions. Supercomplexes were obtained by solubilization of U. maydis mitochondria with digitonin and separated by blue native polyacrylamide gel electrophoresis (BN-PAGE). The molecular mass of supercomplexes and their probable stoichiometries were 1200 kDa (I1:IV1), 1400 kDa (I1:III2), 1600 kDa (I1:III2:IV1), and 1800 kDa (I1:III2:IV2). Concerning the ATP synthase, approximately half of the protein is present as a dimer and half as a monomer. The distribution of respiratory supercomplexes was the same in all growth conditions. We did not find evidence for the association of complex II and the alternative NADH dehydrogenases with other respiratory complexes.

scholarly journals Crystallographic structure of the turbine C-ring from spinach chloroplast F-ATP synthase

2014 ◽  
Vol 34 (2) ◽  
Author(s):  
Asha Manikkoth Balakrishna ◽  
Holger Seelert ◽  
Sven-Hendric Marx ◽  
Norbert A. Dencher ◽  
Gerhard Grüber
Keyword(s):  
Atp Synthase ◽  
Ring Width ◽  
Atp Synthesis ◽  
Crystallographic Structure ◽  
Unit Cell Parameters ◽  
Subunit C ◽  
Cell Parameters ◽  
Ring Diameter ◽  
C Subunit

In eukaryotic and prokaryotic cells, F-ATP synthases provide energy through the synthesis of ATP. The chloroplast F-ATP synthase (CF1FO-ATP synthase) of plants is integrated into the thylakoid membrane via its FO-domain subunits a, b, b’ and c. Subunit c with a stoichiometry of 14 and subunit a form the gate for H+-pumping, enabling the coupling of electrochemical energy with ATP synthesis in the F1 sector. Here we report the crystallization and structure determination of the c14-ring of subunit c of the CF1FO-ATP synthase from spinach chloroplasts. The crystals belonged to space group C2, with unit-cell parameters a=144.420, b=99.295, c=123.51 Å, and β=104.34° and diffracted to 4.5 Å resolution. Each c-ring contains 14 monomers in the asymmetric unit. The length of the c-ring is 60.32 Å, with an outer ring diameter 52.30 Å and an inner ring width of 40 Å.

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