Sarah M. Tschampel

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A new derivation of the GLYCAM06 force field, which removes its previous specificity for carbohydrates, and its dependency on the AMBER force field and parameters, is presented. All pertinent force field terms have been explicitly specified and so no default or generic parameters are employed. The new GLYCAM is no longer limited to any particular class of(More)
The hydration behavior of two model disaccharides, methyl-alpha-D-maltoside (1) and methyl-alpha-D-isomaltoside (2), has been investigated by a comparative 10 ns molecular dynamics study. The detailed hydration of the two disaccharides was described using three force fields especially developed for modeling of carbohydrates in explicit solvent. To validate(More)
We have performed a series of first-principles electronic structure calculations to examine the reaction pathways and the corresponding free energy barriers for the ester hydrolysis of protonated cocaine in its chair and boat conformations. The calculated free energy barriers for the benzoyl ester hydrolysis of protonated chair cocaine are close to the(More)
The inclusion of zero-mass point charges around electronegative atoms, such as oxygen, within molecular mechanical force fields is known to improve hydrogen-bonding directionality. In parallel, inclusion of lone-pairs (LPs) in the TIP5P water model increased its ability to reproduce both gas-phase and condensed-phase properties over its non-LP predecessor,(More)
The hydration behavior of two model disaccharides, methyl-D-maltoside (1) and methyl-Disomaltoside (2), has been investigated by a comparative 10 ns molecular dynamics study. The detailed hydration of the two disaccharides was described using three force fields especially developed for modeling of carbohydrates in explicit solvent. To validate the(More)
Asparagine-linked glycosylation, the co-translational covalent attachment of carbohydrates to asparagine side chains, has a major effect on the folding, stability, and function of many proteins. The carbohydrate composition in mature glycoproteins is heterogeneous due to modification of the initial oligosaccharide by glycosidases and glycosyltransferases(More)
Water-mediated interactions play a key role in carbohydrate-lectin binding, where the interactions involve a conserved water that is separated from the bulk solvent and present a bridge between the side chains of the protein and the carbohydrate ligand. To apply quantum mechanical methods to examine the role of conserved waters, we present an analysis in(More)
The shortage of organs for transplantation into human patients continues to be a driving force behind research into the use of tissues from non-human donors, particularly pig. The primary barrier to such xenotransplantation is the reaction between natural antibodies present in humans and Old World monkeys and the Gal alpha(1-3)Gal epitope (xenograft(More)
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