title: Structure and dynamics of oligonucleotides in the gas phase.
abstract: 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.
authors.affiliation: Institute for Research in Biomedicine (IRB Barcelona), Joint BSC-CRG-IRB Program on Computational Biology, Barcelona (Spain).
authors.forename: Annalisa
authors.initials: A
authors.lastname: Arcella
authors.forename: Jens
authors.initials: J
authors.lastname: Dreyer
authors.forename: Emiliano
authors.initials: E
authors.lastname: Ippoliti
authors.forename: Ivan
authors.initials: I
authors.lastname: Ivani
authors.forename: Guillem
authors.initials: G
authors.lastname: Portella
authors.forename: Valérie
authors.initials: V
authors.lastname: Gabelica
authors.forename: Paolo
authors.initials: P
authors.lastname: Carloni
authors.forename: Modesto
authors.initials: M
authors.lastname: Orozco
mesh_terms: D005740:Gases / Q000138:chemical synthesis*; D015394:Molecular Structure; D009841:Oligonucleotides / Q000737:chemistry*
chemical_list: D005740:Gases; D009841:Oligonucleotides
keywords: DNA; ab initio calculations; gas phase; mass spectrometry; molecular dynamics