Maximal velocity (Vmax) of ATP synthase at 37°C

Range ~350 Revolutions/sec
Organism Bacteria Escherichia coli
Reference Ueno H, Suzuki T, Kinosita K Jr, Yoshida M. ATP-driven stepwise rotation of FoF1-ATP synthase. Proc Natl Acad Sci U S A. 2005 Feb 1 102(5):1333-8 Abstract & p.1337 right column bottom paragraphPubMed ID15668386
Method "Rotation was probed with an 80-nm bead attached to the ring of c subunits in the immobilized FoF1 and recorded with a submillisecond fast camera."
Comments "The rotation rates at various ATP concentrations obeyed the curve defined by a Km of approximately 30 microM and a Vmax of approximately 350 revolutions per second (at 37 degrees C)." "Firstly, FoF1 rotates as fast as 350 rps (37°C). [Researchers] observed rotations at 25°C and 45°C and obtained the Vmax rotation rates of ˜230 and ˜650 rps, respectively. Therefore, extrapolated rotation rate at 60°C, an optimum growth temperature of Bacillus PS3, can reach ˜1,600 rps. Although reservation is needed concerning whether these enormous numbers are really the case, it is certain that the rotation rate of thermophilic FoF1 at 25°C is much faster than the rotation rate (19 ms/120°, that is, 17 rps, at 23°C) reported for E. coli FoF1 reconstituted into liposomes measured with fluorescence resonance energy transfer (ref 22)."
Entered by Uri M
ID 104890