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Accueil > Séminaires > 2013

Simulations of tautomerism in DNA

Denis Jacquemin, CEISAM (Nantes)

Séminaire LCPQ

Salle 20 RC

The investigation of the tautomeric equilibria in guanine-sine base pairs is crucial to understand DNA’s mutations. In these tautomeric equilibria the bases pairs exchange one or more proton(s) through proton transfer (PT) reactions, which eventually leads to so-called rare tautomeric forms.

In this talk I will review our work on the study of the PT mechanisms in both undamaged and perturbed DNA, with a focus on the influence of pi-stacking and solvent effects that have been appraised by combining QM/MM calculations to a doubled stranded DNA fragment.

It is well known that external agents — as metals, radicals and intense electric fields — alter the DNA’s electronic structure, so I will discuss how these external perturbation can modify the natural tautomeric equilibria. Among them, electric fields emerge as an interesting candidate to selectively accumulate genetic error in DNA with exciting applications in biochemistry or medicine.