title: Protein-Style Dynamical Transition in a Non-Biological Polymer and a Non-Aqueous Solvent.
abstract: Temperature-dependent onset of apparent anharmonicity in the microscopic dynamics of hydrated proteins and other biomolecules has been known as protein dynamical transition for the last quarter of a century. Using neutron scattering and molecular dynamics simulation, techniques most often associated with protein dynamical transition studies, we have investigated the microscopic dynamics of one of the most common polymers, polystyrene, which was exposed to toluene vapor, mimicking the process of protein hydration from water vapor. Polystyrene with adsorbed toluene is an example of a solvent-solute system, which, unlike biopolymers, is anhydrous and lacks hydrogen bonding. Nevertheless, it exhibits the essential traits of the dynamical transition in biomolecules, such as a specific dependence of the microscopic dynamics of both solvent and host on the temperature and the amount of solvent adsorbed. We conclude that the protein dynamical transition is a manifestation of a universal solvent-solute dynamical relationship, which is not specific to either biomolecules as solute, or aqueous media as solvent, or even a particular type of interactions between solvent and solute.
authors.affiliation: Chemical and Engineering Materials Division, Neutron Sciences Directorate, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
authors.forename: E
authors.initials: E
authors.lastname: Mamontov
authors.affiliation: Biology and Soft Matter Division, Neutron Sciences Directorate, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.|Solid State Physics Division, Bhabha Atomic Research Centre , Mumbai 400085, India.
authors.forename: V K
authors.initials: VK
authors.lastname: Sharma
authors.affiliation: Neutron Data Analysis and Visualization Division, Neutron Sciences Directorate, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831, United States.
authors.forename: J M
authors.initials: JM
authors.lastname: Borreguero
authors.affiliation: National Institute of Standards and Technology Center for Neutron Research , Gaithersburg, Maryland 20899, United States.|Department of Materials Science and Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors.forename: M
authors.initials: M
authors.lastname: Tyagi
mesh_terms: D000327:Adsorption; D056004:Molecular Dynamics Simulation; D033363:Neutron Diffraction; D011137:Polystyrenes / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D014050:Toluene / Q000737:chemistry*
chemical_list: D011137:Polystyrenes; D011506:Proteins; D012997:Solvents; D014050:Toluene