DNA forms nano piston

DNA is a molecule of many talents. In addition to its biological role of carrying the blueprint to life, it has performed computations and self-assembled into various shapes in the laboratory. Some of those shapes are movable, which paves the way for molecular machines.

Researchers from the French National Museum Of Natural History have constructed a DNA molecule that stretches and shrinks, cycling from an elongated double strand to a more tightly coiled four-strand form. The researchers used a 21-base strand of DNA that measured 7 nanometers elongated and 1.5 in the tightly coiled position.

The researchers calculated that the force exerted by the change was about 8 piconewtons. That's about 100 billionths of the force of a falling apple. Previous research has yielded DNA machines that rotate and that open and close like scissors.

The DNA piston could eventually be used to control nanorobotic systems and to perform calculations in DNA computers. The work appeared in the January 27, 2003 issue of the Proceedings of the National Academy of Sciences. -TECHNOLOGY RESEARCH NEWS