March 15, 2006

Scientist Does ‘Origami’ Folding with DNA

LONDON -- A research scientist in the United States has taken the art of "origami" folding to new heights -- using not paper but DNA.

Paul Rothemund of the California Institute of Technology in Pasadena said on Wednesday he had woven strands of DNA into two-dimensional shapes that could be important in the design of nanodevices measuring only a few billionths of a meter across.

"The construction of custom DNA origami is so simple that the method should make it much easier for scientists from diverse fields to create and study complex nanostructures they might want," he said in a statement on Wednesday.

Nanotechnology involves manipulating materials on a molecular or atomic scale. One nanometre is a billionth of a meter, or about 80,000 times smaller than the width of a human hair.

In nature such molecular machines perform biological functions such as moving muscles and photosynthesis. The technology is already being used in cosmetics, computer chips, self-cleaning windows and stain-resistant clothes.

Rothemund, who described his DNA origami in the latest edition of the journal Nature, has constructed DNA objects as diverse as a triangle, five-pointed star, a smiley face and a tiny map of the Americas smaller than a typical bacterium.

"A biologist might use DNA origami to take proteins which normally occur separately in nature, and organize them into a multi-enzyme factory that hands a chemical product from one enzyme machine to the next in the manner of an assembly line," said Rothemund.

The process includes choosing a shape, using long DNA strands folded to form a scaffold of it, stapling it together with computer-generated short DNA strands and refining it on a computer.

"The results that emerge are stunning," Lloyd Smith, of the University of Wisconsin in Madison, said in a commentary on the research in the journal.