Structure and dynamics of biomolecules by two-dimensional ultraviolet spectroscopy.

Two-dimensional (2D) nuclear magnetic resonance is a diagnostic technique that has revolutionized structural biology. A wealth of spectroscopic information can be obtained by extrapolating 2D techniques to the optical frequency domain, using ultra-short light pulses. 2D electronic spectroscopy (2DES) allows fundamentally new insights into the structure and dynamics of multi-chromophore systems, by measuring how the electronic states of chromophores interact with one another and transfer electronic excitations. Due to technical difficulties, 2DES has been limited so far to the visible range, while most biomolecules absorb in the ultraviolet (UV). This project aims at extending 2DES to the challenging and still uncharted UV-domain and applying it to the study of the photo-physics of genomic systems and of the secondary structure of proteins. Nature has engineered DNA molecules to be photo-stable, so that harmful photochemical processes are minimized. 2DES will unravel the molecular mechanisms of the photo-induced electronic intra/inter-chromophore events in DNA, exposing the energy dissipation pathways which are responsible for its photoprotection. 2DES will be also established as a new diagnostic tool for structural studies of polypeptides and proteins, relying on the UV absorbing peptide bonds and aromatic residues, the latter acting as native local structural probes. 2DES will provide sensitive information on the misfolding/aggregation processes responsible for a wide class of diseases, with the speed of standard optical techniques but with a much greater information content. This will bridge the experimental gap between crude estimates of protein unfolding and full structure determination, enabling rapid assessment of which variants are worth of deeper structural studies. To realize the full power of 2DES, experiments will be combined with simulations and electronic calculations that are necessary to correlate the data with molecular states and structures.

Politecnico di Milano (Italy) 

Other participants
- Dip. di Chimica "G. Ciamician"
- Resp. Scientifico: Dr. Marco Garavelli

Start date 01/04/2012
End date 31/03/2017
Duration 60 months
Project Reference 291198
Project cost 2.493.000 EURO
Project Funding 2.493.000 EURO
Area FP7-IDEAS-ERC-Advanced
Subprogramme Area ERC Advanced Grant - Physical and Analytical Chemical sciences
Contract type Support for frontier research-ERC Advanced Co-Investigator Grant