Frederick D. Lewis, George C. Schatz, Michael R. Wasielewski (all at Northwestern University), Torsten Fiebig (Boston College) and Alexander L. Burin (Tulane University) are jointly supported for research into the electronic structure of DNA. More specific objectives include the investigation of the nuclear and electronic structure of short, well-defined duplex base pair domains in both the ground and electronically excited states; and investigation of the structural and electronic changes which occur upon the oxidation or reduction of duplex domains. The team will study short stable base pair domains in custom-designed hairpin and dumbbell structures. A wide range of state-of-the-art time-resolved spectroscopic, computational, and structural techniques will be used to probe how the structural changes within DNA are coupled to the properties of excited and ion states within it. Experimental approaches include molecular design and synthesis, spectroscopy, time-resolved transient absorption spectroscopy, time-resolved EPR spectroscopy, molecular dynamics, time-resolved circular dichroism, and electronic structure calculations. David Tiede (Argonne National Laboratory) will also collaborate with the team and bring expertise in time-resolved diffraction techniques.
The structural and functional integrity of DNA is critical to its role in biology, so that this project will provide fundamental information on how light and chemical agents introduce reactive sites within DNA, which change its structure and potentially alter its function. The anticipated outcomes of this collaboration include elucidation of the properties of neutral and ionized short DNA base-pair domains, training of undergraduate and graduate students in an important interdisciplinary area, and providing a model for interlocking collaboration among investigators with varying experience and in different research environments. This project is supported by the Collaborative Research in Chemistry Program.