Send to

Choose Destination
J Biol Chem. 1990 Jan 5;265(1):171-6.

Kinetics of ATP and inorganic phosphate release during hydrolysis of ATP by rabbit skeletal actomyosin subfragment 1. Oxygen exchange between water and ATP or phosphate.

Author information

Division of Physical Biochemistry, National Institute for Medical Research, London, United Kingdom.


We have used the technique of phosphate: water oxygen exchange to measure the rate of ATP and Pi release and Pi binding to myosin subfragment 1 and actomyosin subfragment 1 from rabbit skeletal muscle. The oxygen exchange distributions for ATP and Pi release fit a simple kinetic model with a single set of rate constants for each step. For actomyosin subfragment 1 (20 degrees C, pH 7.0, I = 50 mM), the rate constant governing ATP release is approximately 8 s-1, Pi release is at approximately 60 s-1 and Pi rebinds to an ADP state at greater than 120 M-1 s-1. These rate constants are similar to those that may occur for undistorted cross-bridges within glycerinated rabbit psoas fibers (Bowater, R., Webb, M. R., and Ferenczi, M. A. (1989) J. Biol. Chem. 264, 7193-7201.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center