title: Hydration-dependent dynamics of human telomeric oligonucleotides in the picosecond timescale: a neutron scattering study.
abstract: The dynamics of the human oligonucleotide AG3(T2AG3)3 has been investigated by incoherent neutron scattering in the sub-nanosecond timescale. A hydration-dependent dynamical activation of thermal fluctuations in weakly hydrated samples was found, similar to that of protein powders. The amplitudes of such thermal fluctuations were evaluated in two different exchanged wave-vector ranges, so as to single out the different contributions from intra- and inter-nucleotide dynamics. The activation energy was calculated from the temperature-dependent characteristic times of the corresponding dynamical processes. The trends of both amplitudes and activation energies support a picture where oligonucleotides possess a larger conformational flexibility than long DNA sequences. This additional flexibility, which likely results from a significant relative chain-end contribution to the average chain dynamics, could be related to the strong structural polymorphism of the investigated oligonucleotides.
authors.affiliation: Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Sebastiani
authors.affiliation: Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Longo
authors.affiliation: Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Orecchini
authors.affiliation: Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Comez
authors.affiliation: CNR-IOM OGG c/o Institut Laue-Langevin, 71 Avenue des Martyrs, CS20156, 38042 Grenoble Cedex 9, France.
authors.forename: A
authors.initials: A
authors.lastname: De Francesco
authors.affiliation: Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at Heinz Maier-Leibnitz Zentrum, Lichtenbergstrasse 1, 85747 Garching, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Muthmann
authors.affiliation: EPSAM, Keele University, Staffordshire ST5 5BG, United Kingdom.
authors.forename: S C M
authors.initials: SC
authors.lastname: Teixeira
authors.affiliation: Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Petrillo
authors.affiliation: Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Sacchetti
authors.affiliation: Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, Via A. Pascoli, 06123 Perugia, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Paciaroni