WWU researchers furnish DNA with tiny "wire" / Natural DNA structure preserved

The DNA biomolecule, responsible in nature for storing hereditary information, is being used increasingly as a component in nanotechnology. One successful approach for producing functional nanostructures from DNA is to insert metal ions into an artificial DNA double helix, which serves as a framework.

“If several metal ions are arranged next to each other in this way,” says Prof. Jens Müller from the Institute of Inorganic and Analytical Chemistry at WWU, “a molecule is produced which incorporates, so to speak, a one-dimensional wire.” Together with researchers from the University of Zurich, his team has now produced an artificial DNA with a razor-thin “wire” inside, demonstrating in the process that the natural structure is preserved.

Prof. Müller's team replaced some of the so-called nucleobases, found inside each DNA spiral, with artificial components. “In the case of the DNA we have created, these artificial components are able to bind extremely tightly to silver ions,” says Prof. Müller. “As a result, we have succeeded in arranging three silver ions directly next to each other inside the spiral, like a string of pearls.” What's special about the structure of the DNA helix, which was determined in collaboration with researchers at the Institute of Inorganic Chemistry at the University of Zurich, is the fact that the form of the spiral is hardly changed through the insertion of the metal ions. “Such information about the structure is enormously important for the further development of functionalized DNA,” comments Prof. Müller.

Before the artificial DNA can be used in future as a nanowire or nanomagnet – or in analytics, e.g. to ascertain the existence of heavy metals in tap-water – further physical properties must first be examined in detail, now that the structure has been successfully clarified.

Jens Müller has been Professor of Inorganic Chemistry at the WWU Münster since 2008. Before that he was a beneficiary of the Emmy Noether Programme for outstanding junior research staff at universities. Since January 2010 he has also been heading a subproject in the Collaborative Research Centre 858 – “Synergistic Effects in Chemistry: From Additivity to Cooperativity”.

Reference: Johannsen S. et al. (2010): Solution structure of a DNA double helix with consecutive metal-mediated base pairs; Nature Chemistry, Published online: 17 January 2010 | doi:10.1038/nchem.512