"This is the first translational system based on a rotary nanomechanical device," Ned Seeman of New York University told nanotechweb.org. "It prototypes the translation of one type of information into another type of information. It is a major advance in our ability to control the structure of matter on the nanometre scale."
Seeman's device, which measured roughly 110 x 30 x 2 nm, contained two DNA PX-JX2 devices. Seeman developed these DNA machines a couple of years ago - they assume one of two structural states depending on which pair of DNA set strands binds to the device.
Seeman and colleague Shiping Liao added strands of DNA to set up the state of each of the PX-JX2 devices. Then they added DNA double-crossover (DX) molecules. These both provided components for the final product and acted as an adapter between these components and the device.
In this way, the scientists used the machine to make one of four specific DNA sequences, or product molecules. Although in this case the team chose DNA to prototype the device, it could also assemble other product molecules.
The nanomachine is analagous to a strand of mRNA, which directs the synthesis of a particular polypeptide chain in an organism, according to its make-up. But there is a key difference.
Unlike a ribosome, Seeman's device cannot translocate. As a result, it can only make products that are pretty much the same size as itself. The team believes that future versions of the device could be able to incorporate translocation.
"The main application I foresee is the construction of new materials that will be coded by DNA signals and then prepared by the nanomechanical system," said Seeman. "Ultimately, we will be able to make polymers and new materials of remarkable diversity and with features never seen before."
The researchers reported their work in Science.