SCIENCE News This Week
November 24 2000, 290 (5496)
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Robert F. Service

Devens Gust, a chemist at Arizona State University in Tempe, and a handful of colleagues have built tiny refineries that convert the energy in sunlight to chemical fuel to power nanomachines. The fuel in this case is adenosine triphosphate, the same energy-rich molecule that powers chemical reactions inside cells. At last August's meeting of the American Chemical Society in Washington, D.C., Gust reported that he and his colleagues had collaborated with other groups to run their protein-based molecular machines on little more than sunlight.

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Harnessing Biomotors

SCIENCE, Volume 290, Issue 5496

The F1-ATPase enzyme undergoes rotary motion when it uses adenosine triphosphate as an energy source, and previous studies have imaged this motion by attaching actin filaments to the enzyme's central subunit. Soong et al. (p. 1555) have now harnessed this enzyme to drive inorganic propellers. Appropriately tagged enzymes were attached to the tops of an array of nanometer-scale nickel posts and, in turn, nickel propellers, 150 nanometers (nm) in diameter and 750 to 1400 nm in length, were attached to the tops of the "motors." Although such assembly is not foolproof (only a small fraction of motors are viable), some can be seen to drive currents in the surrounding solution for more than 2 hours while being fed ATP.