Reparameterization of Solute-Solute Interactions for Amino Acid-Sugar Systems Using Isopiestic Osmotic Pressure Molecular Dynamics Simulations.
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ABSTRACT:
SUBMITTER: Lay WK
PROVIDER: S-EPMC5844349 | biostudies-literature | 2017 May
REPOSITORIES: biostudies-literature
Publications
Reparameterization of Solute-Solute Interactions for Amino Acid-Sugar Systems Using Isopiestic Osmotic Pressure Molecular Dynamics Simulations.
Lay Wesley K WK Miller Mark S MS Elcock Adrian H AH
Journal of chemical theory and computation 20170428 5
AMBER/GLYCAM and CHARMM are popular force fields for simulations of amino acids and sugars. Here we report excessively attractive amino acid-sugar interactions in both force fields, and corrections to nonbonded interactions that match experimental osmotic pressures of mixed aqueous solutions of diglycine and sucrose. The modified parameters also improve the ΔG<sub>trans</sub> of diglycine from water to aqueous sucrose and, with AMBERff99SB/GLYCAM06, eliminate a caging effect seen in previous sim ...[more]
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