Wow.
Scientists have demonstrated a way to harness the motion of swimming bacteria to turn tiny gears. This bacteria-driven mechanism could someday power micro-machines that combine living organisms and man-made materials.
To build their rudimentary device, the research team first fashioned silicon gears measuring a mere 0.01 inches (380 micrometers) across and 0.002 inches (50 micrometers) thick. With their slanted teeth, the gears look rather like tiny ninja stars.
The microgears were then placed into a nutrient broth swarming with the microbe Bacillus subtilis, the workhorses in this setup. When supplied with nutrients and oxygen the bacteria scoot about randomly.
