title: Thermodynamics of Hydrophobic Amino Acids in Solution: A Combined Experimental-Computational Study.
abstract: We present a joint experimental-computational study to quantitatively describe the thermodynamics of hydrophobic leucine amino acids in aqueous solution. X-ray scattering data were acquired at a series of solute and salt concentrations to effectively measure interleucine interactions, indicating that a major scattering peak is observed consistently at q = 0.83 Å-1. Atomistic molecular dynamics simulations were then performed and compared with the scattering data, achieving high consistency at both small and wider scattering angles (q = 0-1.5 Å-1). This experimental-computational consistence enables a first glimpse of the leucine-leucine interacting landscape, where two leucine molecules are aligned mostly in a parallel fashion, as opposed to antiparallel, but also allows us to derive effective leucine-leucine interactions in solution. Collectively, this combined approach of employing experimental scattering and molecular simulation enables quantitative characterization of effective intermolecular interactions of hydrophobic amino acids, critical for protein function and dynamics such as protein folding.
authors.affiliation: State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University , Beijing 100871, China.|Department of Nutrition, Case Western Reserve University , Cleveland, Ohio 44106, United States.
authors.forename: Lingshuang
authors.initials: L
authors.lastname: Song
authors.affiliation: Photon Sciences Directorate, Brookhaven National Laboratory , Upton, New York 11973, United States.
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University , Beijing 100871, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Meng
authors.affiliation: Department of Nutrition, Case Western Reserve University , Cleveland, Ohio 44106, United States.
authors.forename: Sichun
authors.identifier: http://orcid.org/0000-0002-1726-0576
authors.initials: S
authors.lastname: Yang