A motor that drives flagellars of bacteria.
The energy source of flagellar movement of a bacterium is the
electrochemical potential difference between hydrogen ion concentrations in and out of the cell.
The rotary part of a flagellum is the only organ that makes a rotary motion among all living things
on the earth, and is the smallest motor ever known. The structure is a chemical motor consisting of
fiber, a hook, and the base. It is considered that the torque arises from the inward flow of
hydrogen ions from outside the cell, but the mechanism of converting the flow of ions into rotary
motion is left unknown.
Polymer actuator, Chemical bearing, Mechanochemical actuator