Twisting and Turning DNA to Build Tools for the Body (International Herald Tribune; 13.08.09)

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Researchers at the Dana-Farber Cance Institute and Harvard University have taken a step toward creating parts for molecular machines out of DNA. In a paper in Science, Hendrik Dietz, now with the Technical University of Munich, Shawn M. Douglas and William H. Shih describe twisting and curving DNA into shapes using strands of DNA that self-assemble into rigid bundles, with the individual double helixes joined by strong cross-links. Manipulating the base pairs in the helixes causes the bundles to bend in a specific direction. The goal is to build a machine that could, say, deliver a drug to a precise spot in the body. Henry Fountain

A 12-tooth gear, at about one-tenth of a micrometer, assembled from strands of DNA. Science/AAS

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