The H+/ATP coupling ratio of the ATP synthase from thiol-modulated chloroplasts and two cyanobacterial strains is four.
In this paper the authors emphasise that the proton translocating ATP synthase from thiol-modulated chloroplasts and two cyanobacterial strains has a coupling ratio of 4 protons per ATP synthesised or hydrolysed. This ratio is determined by several thermodynamic studies at equilibrium between phosphate potential (Delta Gp) and proton gradient (Delta(mu)H+), and is confirmed by measurement of proton flux during ATP hydrolysis. Ratios lower than 4 H+/ATP that have been published in the past have predominantly been determined with the oxidised chloroplast enzyme. Errors in these measurements will be discussed.
Van Walraven
H S
HS
Department of Physiology and Biochemistry of Plants, Institute for Molecular Biological Sciences (IMBW), BioCentrum Amsterdam, The Netherlands.
Strotmann
H
H
Schwarz
O
O
Rumberg
B
B
D002736:Chloroplasts / Q000378:metabolism*; D000458:Cyanobacteria / Q000201:enzymology*; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D013816:Thermodynamics
D006180:Proton-Translocating ATPases