Abstract:
:Whereas the laws of thermodynamics prohibit extraction of useful work from the Brownian motion of particles in equilibrium, these motions can be "rectified" under nonequilibrium conditions, for example, in the presence of asymmetric geometrical obstacles. Here, we describe a class of systems in which aerobic bacteria Bacillus subtilis moving randomly in a fluid film power submillimeter gears and primitive systems of gears decorated with asymmetric teeth. The directional rotation is observed only in the regime of collective bacterial swimming and the gears' angular velocities depend on and can be controlled by the amount of oxygen available to the bacteria. The ability to harness and control the power of collective motions appears an important requirement for further development of mechanical systems driven by microorganisms.
journal_name
Proc Natl Acad Sci U S Aauthors
Sokolov A,Apodaca MM,Grzybowski BA,Aranson ISdoi
10.1073/pnas.0913015107subject
Has Abstractpub_date
2010-01-19 00:00:00pages
969-74issue
3eissn
0027-8424issn
1091-6490pii
0913015107journal_volume
107pub_type
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