Posted: June 1, 2010

'Biocomputing' advance demonstrates DNA computing circuits with artificial catalytic nucleic acids

(Nanowerk News) EU-funded scientists have succeeded in demonstrating the feasibility of components for a kind of 'biocomputer', paving the way for new advances in the field of bioengineering. The scientists, from the Chemistry Department at the University of Liège in Belgium and the Institute of Chemistry at the Hebrew University of Jerusalem in Israel, set out the details of their work in an article in the journal Nature Nanotechnology ("DNA computing circuits using libraries of DNAzyme subunits").
EU support for the research came from the MOLOC ('Molecular logic circuits') project, which received just over EUR 2 million of its EUR 2.67 million budget from the 'Information and communication technologies' (ICT) Theme of the Seventh Framework Programme (FP7).
For the study, led by Professor Itamar Willner of the Hebrew University of Jerusalem, the researchers theoretically developed and experimentally demonstrated that artificial catalytic nucleic acids known as DNAzymes and their substrates can form a viable platform for the logic operations that are key to computational processes.
The work could aid in the development of applications in nanomedicine, for example, where the ability to carry out logic operations at the molecular level could facilitate the analysis of a disease and trigger the response of therapeutic agents.
'Biological systems that are capable of performing computational operations could be of use in bioengineering and nanomedicine, and DNA [deoxyribonucleic acid] and other biomolecules have already been used as active components in biocomputational circuits,' the researchers write.
'However, for biocomputational circuits to be useful for applications it will be necessary to develop a library of computing elements, to demonstrate the modular coupling of these elements, and to demonstrate that this approach is scalable.'
The Belgian-Israeli team created a DNA-based computational platform that draws on two libraries of nucleic acids, one of which is made up of subunits of DNAzymes. The second library comprises the DNAzymes' substrates.
'We demonstrate that the library of DNAzymes, designed and synthesised by Professor Willner's team, allows for the realisation of a complete ensemble of logic gates which can be used to compute any Boolean function,' explained Françoise Remacle of the University of Liège, who is also the MOLOC project coordinator.
'We also show that [the] dynamic assembly [of these gates] into circuits can be directed by selective inputs. Moreover, the design allows for the amplification of outputs.'
The MOLOC project got underway at the beginning of 2008 and is scheduled to draw to a close at the end of this year. The aim of the initiative is to design and demonstrate the feasibility and advantages of logic circuits in which the basic element is a single molecule (or assemblies of atoms or molecules) acting as a logic circuit. These systems differ from those that use a molecule as a switch.
In addition to the University of Liège and the Hebrew University of Jerusalem, MOLOC's project partners are the Institute of Solid State Research (IFF) at the Forschungszentrum Jülich, the Max Planck Institute for Quantum Optics, the Department of Chemistry at Heinrich-Heine University Düsseldorf, the Institute of Applied Optics at the Technische Universität Darmstadt in Germany, all based in Germany, and the Kavli Institute of Nanoscience at Delft University of Technology in the Netherlands. <
Source: Cordis