Turnover number of F1F0 ATP synthase when inactivating a percentage of the ATPase with DCCD (N,N-dicyclohexylcarbodiimide)

Value 270 sec^-1 Range: ±40 sec^-1
Organism Bacteria Escherichia coli
Reference Tomashek JJ, Glagoleva OB, Brusilow WS. The Escherichia coli F1F0 ATP synthase displays biphasic synthesis kinetics. J Biol Chem. 2004 Feb 6 279(6):4465-70 DOI: 10.1074/jbc.M310826200 p.4469 left columnPubMed ID14602713
Primary Source [18] Etzold C, Deckers-Hebestreit G, Altendorf K. Turnover number of Escherichia coli F0F1 ATP synthase for ATP synthesis in membrane vesicles. Eur J Biochem. 1997 Jan 15 243(1-2):336-43.PubMed ID9030757
Method Primary source abstract: "In parallel, the amount of F0F1 complexes present in membrane vesicles was determined by immunoquantitation to be 3.3 +/- 0.3% of the membrane protein for cells grown in rich medium and 6.6 +/- 0.3% for cells grown in minimal medium with glycerol as sole carbon and energy source. Based on these data, a turnover number for ATP synthesis of 270 +/- 40 s^(-1) could be determined in the presence of 5% active F0F1 complexes."
Comments P.4469 left column: "Using an innovative approach they [Etzold et al., 1997, primary source] tested the hypothesis that the lower value produced by the E. coli ATPase was caused by an imbalance between the amount of enzyme and the respiratory capacity of the vesicles and that far more synthase existed than could be activated by the respiratory chain. In support of this hypothesis, they demonstrated that the turnover could be increased to 270 s^-1 by inactivating a percentage of the ATPase with DCCD in order to produce a greater respiratory driving force for the remaining active, unmodified enzymes."
Entered by Uri M
ID 115178