Motion control of single F1-ATPase rotary biomolecular motor using microfabricated local heating devices

Biomolecular motors are major targets in single-molecule studies, which reveal molecular behaviors usually hidden in the emsemble- and time-averaging of bulk experiments. Methods for rapid experimental condition control during single-biomolecule observation are a key technology to elucidate the molecular mechanisms of proteins. One of the most promising methods is real-time rapid temperature alternation. A microheater and a microthermosensor were integrated on the glass plate for controlling the temperature locally; the maximum response speeds were 71.5 and 56.9K∕s for temperature rise and fall, respectively. Rapid temperature alternation with microfabricated thermodevice allowed rapid and reversible angular velocity control of a single F1-ATPase, a rotary biomolecular motor. The rapid control of the temperature enabled us to perform rotation assay at temperatures higher than that would “normally” denature them. This revealed that the torque of F1-ATPase seems to increase at higher temperatures with the increasing rate of 4% per 10°C. This method and knowledge for controlling the biomolecular motor can also be applied to future hybrid organic-inorganic nanosystems, which use biomolecular motors as nanoactuators.