Electronic structure of DNA revealed – may lead to easier sequencing of DNA

The Hebrew University of Jerusalem scientists and others have revealed for the first time the electronic structure of single DNA molecules.  In their work, the researchers were able to decode the electronic structure of DNA and to understand how the electrons distribute into the various parts of the double helix, a result that has been pursued by scientists for many years, but was previously hindered by technical problems.

The knowledge that has been acquired in this project may also be relevant for current attempts to develop new sophisticated, reliable, faster and cheaper ways to decode the sequence of human DNA.

Finding the electronic structure of DNA was made possible by a collaboration between experimental and theoretical scientists who worked with long and homogeneous DNA molecules at minus 195 degrees Celsius, using a scanning tunneling microscope (STM) to measure the current that passes across a molecule deposited on a gold substrate. Then, by means of theoretical calculations based on the solution of quantum equations, the electronic structure of DNA corresponding to the measured current was obtained.

The knowledge of the electronic properties of DNA is an important issue in many scientific areas from biochemistry to nanotechnology.  For example, in the study of DNA damage by ultraviolet radiation, UV radiation may cause the generation of free radicals and genetic mutations. In those cases, DNA repair occurs spontaneously via an electronic charge transfer along the DNA helix that restores the damaged molecular bonds.

Elaine Warburton  www.geneticsandhealth.com