The same molecule that provides the instructions for building life may one day be used to build computers.
Using copper and a common ingredient of shampoo, scientists were able to turn DNA into a sort of molecular switch, they report in the journal Chemical Communications. This ability could one day make it possible for DNA to play the role that a diode or transistor plays in electronic circuits.
"Our research shows how the structure of our genetic material — DNA — can be changed and used in a way we didn't realize. A single switch was possible before — but we show for the first time how the structure can be switched twice," lead researcher Zoë Waller of the University of East Anglia said in a statement.
Scientists previously found that DNA folds into a structure known as an i-motif when exposed to acids. This new work shows that adding copper cations — positively charged copper molecules — to DNA in the i-motif conformation causes it to fold into a hairpin-shaped structure.
The key advantage of folding the DNA into this hairpin structure is its reversibility. The researchers found that the DNA will fold back into the i-motif when exposed to a chemical called ethylenediaminetetraacetic acid (EDTA), which may be among the list of unpronounceable ingredients on the back of your shampoo bottle.
In today's electronics, diodes or transistors typically serve as the "logic gates," which are essentially switches, in circuits. The ability to flip back and forth between the hairpin and the i-motif conformations makes DNA a kind of switch that might be able to serve the same purpose.
"This research expands how DNA could be used as a switching mechanism for a logic gate in DNA-based computing or in nano-technology," Waller said in a statement.
The advance comes on the heels of a separate finding presented at the National Meeting & Exposition of the American Chemical Society on Monday that demonstrated the advantages of DNA's longevity for storing information. In this scenario, the DNA would serve the role of hard drive rather than diode or transistor.
Beyond computing, the knowledge that copper cations cause specific changes to the structure could enable the molecule to serve yet another purpose, the researchers suggest. Copper cations are very toxic to aquatic organisms, including fish, and exploiting this property of DNA may be a useful way to detect these contaminants with introducing other potentially harmful substances.
Photo: Mehmet Pinarci | Flickr