H+/ATP ratio

Range 4.0±0.3 H+/ATP
Organism Bacteria Escherichia coli
Reference Petersen J, Förster K, Turina P, Gräber P. Comparison of the H+/ATP ratios of the H+-ATP synthases from yeast and from chloroplast. Proc Natl Acad Sci U S A. 2012 Jul 10 109(28):11150-5. doi: 10.1073/pnas.1202799109. p.11154 left column paragraph above bottomPubMed ID22733773
Method p.11153 left column bottom paragraph:"In this work, the H+/ATP ratios of the yeast mitochondrial MF0F1 and of the chloroplast CF0F1 were measured in a simple chemiosmotic system, constituted by liposomes with the membrane-integrated enzymes."
Comments p.11154 left column paragraph above bottom:"Recently [investigators] have used the same method to compare the H+/ATP ratios of the ATP synthases from Escherichia coli and from chloroplasts (ref 19). [They] found that H+/ATP = 4.0 ± 0.2 for CF0F1, in accordance with the present data, and H+/ATP = 4.0 ± 0.3 for EF0F1. However, the c-subunit stoichiometry in EF0 is not exactly known, because numbers between 12 (ref 35) and 10 (refs 36, 37) have been reported, and it has also been proposed to vary according to growth conditions (ref 38). Therefore, for the E. coli enzyme, a meaningful comparison between the c/ß ratio and the H+/ATP ratio has to await further structural data."
Entered by Uri M
ID 111522