A. Ishijima et al., Simultaneous measurement of individual ATPase and mechanical reactions by a single myosin molecule at work, OPT REV, 6(1), 1999, pp. 16-23
Based on techniques for single molecule imaging and nanomanipulation by opt
ical tweezers, we have developed a new technique that allows simultaneous m
easurement of individual ATPase and mechanical reactions from a single myos
in molecule during force generation. We show how the ATPase reaction couple
s to the mechanical reaction directly at the single molecule level. The res
ults show that the myosin head can produce force even after releasing the b
ound nucleotide, probably ADP, suggesting that the chemical energy driven b
y ATP hydrolysis can be hysteretically stored in the myosin molecule. This
view does not support a widely accepted hypothesis in which the force gener
ation is tightly coupled to ligand dissociation.