Bacterial Spin Doctors

摘要

A micro-windmill driven by tumbling bacteria has been designed by Luca Angelani and his co-workers at the University of Rome La Sapienza.rnStrikingly, the 'bacterial wind' isn't blowing in any particular direction - a cogwheel rotor converts the uncoordinated impacts of many bacterial cells into directional rotation by means of the asymmetrical, sawtooth shape of its teeth. This makes the 'bacterial motor' akin to Brownian motors, long familiar in physics and biology, in which random motions are converted to directional ones by asymmetry in the environment.