Structure and Dynamics of Oligonucleotides in the Gas Phase
|Title||Structure and Dynamics of Oligonucleotides in the Gas Phase|
|Publication Type||Journal Article|
|Year of Publication||2015|
|Authors||Arcella, Annalisa, Dreyer Jens, Ippoliti Emiliano, Ivani Ivan, Portella Guillem, Gabelica Valérie, Carloni Paolo, and Orozco Modesto|
|Journal||Angewandte Chemie International Edition|
|Keywords||ab initio calculations, DNA, gas phase, Mass Spectrometry, molecular dynamics|
By combining ion-mobility mass spectrometry experiments with sub-millisecond classical and ab initio molecular dynamics we fully characterized, for the first time, the dynamic ensemble of a model nucleic acid in the gas phase under electrospray ionization conditions. The studied oligonucleotide unfolds upon vaporization, loses memory of the solution structure, and explores true gas-phase conformational space. Contrary to our original expectations, the oligonucleotide shows very rich dynamics in three different timescales (multi-picosecond, nanosecond, and sub-millisecond). The shorter timescale dynamics has a quantum mechanical nature and leads to changes in the covalent structure, whereas the other two are of classical origin. Overall, this study suggests that a re-evaluation on our view of the physics of nucleic acids upon vaporization is needed.