Kinetics of Proton-Transport-Coupled ATP Synthesis Catalyzed by the Chloroplast ATP Synthase

1986 ◽  
Vol 90 (11) ◽  
pp. 1034-1040 ◽  
Author(s):  
P. Gräber ◽  
P. Fromme ◽  
U. Junesch ◽  
G. Schmidt ◽  
G. Thulke
Keyword(s):  
Atp Synthase ◽  
Proton Transport ◽  
Atp Synthesis ◽  
Chloroplast Atp Synthase ◽  
Kinetics Of

scholarly journals Proton transport coupled ATP synthesis by the purified yeast H+-ATP synthase in proteoliposomes

2010 ◽  
Vol 1797 (11) ◽  
pp. 1828-1837 ◽  
Author(s):  
Kathrin Förster ◽  
Paola Turina ◽  
Friedel Drepper ◽  
Wolfgang Haehnel ◽  
Susanne Fischer ◽  
...  
Keyword(s):  
Atp Synthase ◽  
Proton Transport ◽  
Atp Synthesis

Steady-state and pre-steady-state kinetics of the mitochondrial F(1)F(o) ATPase: is ATP synthase a reversible molecular machine?

2000 ◽  
Vol 203 (1) ◽  
pp. 41-49 ◽  
Author(s):  
A.D. Vinogradov
Keyword(s):  
Steady State ◽  
Atp Synthase ◽  
Atp Synthesis ◽  
Gamma Subunit ◽  
Change Mechanism ◽  
Steady State Kinetics ◽  
Energy Dependent ◽  
Variable Substrate ◽  
Kinetics Of ◽  
Hydrolysis Of

H(+)-ATP synthase (F(1)F(o) ATPase) catalyzes the synthesis and/or hydrolysis of ATP, and the reactions are strongly affected by all the substrates (products) in a way clearly distinct from that expected of a simple reversibly operating enzyme. Recent studies have revealed the structure of F(1), which is ideally suited for the alternating binding change mechanism, with a rotating gamma-subunit as the energy-driven coupling device. According to this mechanism ATP, ADP, inorganic phosphate (P(i)) and Mg(2+) participate in the forward and reverse overall reactions exclusively as the substrates and products. However, both F(1) and F(1)F(o) demonstrate non-trivial steady-state and pre-steady-state kinetics as a function of variable substrate (product) concentrations. Several effectors cause unidirectional inhibition or activation of the enzyme. When considered separately, the unidirectional effects of ADP, P(i), Mg(2+) and energy supply on ATP synthesis or hydrolysis may possibly be explained by very complex kinetic schemes; taken together, the results suggest that different conformational states of the enzyme operate in the ATP hydrolase and ATP synthase reactions. A possible mechanism for an energy-dependent switch between the two states of F(1)F(o) ATPase is proposed.

The C-Terminal Domain of the ε Subunit of the Chloroplast ATP Synthase Is Not Required for ATP Synthesis†

Biochemistry ◽  
2002 ◽  
Vol 41 (51) ◽  
pp. 15130-15134 ◽  
Author(s):  
Kristine F. Nowak ◽  
Vazha Tabidze ◽  
Richard E. McCarty
Keyword(s):  
Atp Synthase ◽  
Atp Synthesis ◽  
Chloroplast Atp Synthase ◽  
Terminal Domain

scholarly journals Feedback limitation of photosynthesis at high CO2 acts by modulating the activity of the chloroplast ATP synthase

2009 ◽  
Vol 36 (11) ◽  
pp. 893 ◽  
Author(s):  
Olavi Kiirats ◽  
Jeffrey A. Cruz ◽  
Gerald E. Edwards ◽  
David M. Kramer
Keyword(s):  
Electron Transfer ◽  
Atp Synthase ◽  
Atp Synthesis ◽  
Nicotiana Sylvestris ◽  
O2 Evolution ◽  
High Co2 ◽  
Chloroplast Atp Synthase ◽  
Low Co2 ◽  
Photosynthetic Electron Transfer

It was previously shown that photosynthetic electron transfer is controlled under low CO2 via regulation of the chloroplast ATP synthase. In the current work, we studied the regulation of photosynthesis under feedback limiting conditions, where photosynthesis is limited by the capacity to utilise triose-phosphate for synthesis of end products (starch or sucrose), in a starch-deficient mutant of Nicotiana sylvestris Speg. & Comes. At high CO2, we observed feedback control that was progressively reversed by increasing O2 levels from 2 to 40%. The activity of the ATP synthase, probed in vivo by the dark-interval relaxation kinetics of the electrochromic shift, was proportional to the O2-induced increases in O2 evolution from PSII (JO2), as well as the sum of Rubisco oxygenation (vo) and carboxylation (vc) rates. The altered ATP synthase activity led to changes in the light-driven proton motive force, resulting in regulation of the rate of plastoquinol oxidation at the cytochrome b6f complex, quantitatively accounting for the observed control of photosynthetic electron transfer. The ATP content of the cell decreases under feedback limitation, suggesting that the ATP synthesis was downregulated to a larger extent than ATP consumption. This likely resulted in slowing of ribulose bisphosphate regeneration and JO2). Overall, our results indicate that, just as at low CO2, feedback limitations control the light reactions of photosynthesis via regulation of the ATP synthase, and can be reconciled with regulation via stromal Pi, or an unknown allosteric affector.

ATP Synthesis Driven by a Valinomycine Induced K+ Diffusion Potential in Liposomes Bearing Chloroplast ATP Synthase

1984 ◽  
Vol 39 (3-4) ◽  
pp. 320-321 ◽  
Author(s):  
M. Dinant ◽  
K. Kaminski
Keyword(s):  
Atp Synthase ◽  
Atp Synthesis ◽  
Diffusion Potential ◽  
Chloroplast Atp Synthase

Partially purified chloroplast ATP synthase was reconstituted into asolectin liposomes. A valinomycine induced potassium diffusion potential from outside to inside the vesicles promoted a measurable ATP synthesis. If valinomycine was replaced by nigericine, practically no ATP was formed

Coupling Proton Movement to ATP Synthesis in the Chloroplast ATP Synthase

2005 ◽  
Vol 37 (6) ◽  
pp. 467-473 ◽  
Author(s):  
Mark L. Richter ◽  
Hardeep S. Samra ◽  
Feng He ◽  
Andrew J. Giessel ◽  
Krzysztof K. Kuczera
Keyword(s):  
Atp Synthase ◽  
Atp Synthesis ◽  
Chloroplast Atp Synthase ◽  
Proton Movement
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