Japanese researchers have developed a novel type of engine on a near-microscopic scale that is powered by living bacteria. It’s believed to be the first such device of its type.

Yuichi Hiratsuka and other research­ ers from Japan’s National Institute of Advanced Industrial Science and Tech­ nology crafted the innovative micro motor from silicon.

They used a genetically modified ver­ sion of one of the fastest known micro­ organisms, a "gliding bacterium" called Mycoplasma mobile.

"Mycoplasma is just one example of micro-organisms with interesting and potentially useful properties," Hiratsu­ka tells Web site PhysOrg.com. Future uses, he added, could include construc­ tion of electric-generator systems and even microrobot applications.

The researchers figured out how to make the bacteria crawl in the same direction, following a groove in a tiny rotor. The motion of the bacteria moved the rotor about twice as fast as the speed of a second hand on a clock, sci­ entists say.

Biological motors have several advan­ tages over regular motors. They can be very small and much more efficient in using energy, which has obvious impli­ cations for energy conservation. The motor is essentially fueled by sugar, which is the substance that makes the bacteria grow.

This chemical harnessing of bacteria "adds a new direction to our field," Henry Hess of the University of Florida tells sciencenews.org.

Hess, a bimolecular-motor spe­ cialist, adds, "The micromotor system points the way to self-sustaining and self-repairing machines, since the active units . .. can multiply and replace each other. Living machines rock!"