Ion specificity at the peptide bond: molecular dynamics simulations of N-methylacetamide in aqueous salt solutions
Language English Country United States Media print
Document type Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.
PubMed
20038160
DOI
10.1021/jp910953w
Knihovny.cz E-resources
- MeSH
- Acetamides chemistry MeSH
- Ions chemistry MeSH
- Peptides chemistry MeSH
- Solutions chemistry MeSH
- Molecular Dynamics Simulation MeSH
- Salts chemistry MeSH
- Water chemistry MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Names of Substances
- Acetamides MeSH
- Ions MeSH
- N-methylacetamide MeSH Browser
- Peptides MeSH
- Solutions MeSH
- Salts MeSH
- Water MeSH
Affinities of alkali cations and halide anions for the peptide group were quantified using molecular dynamics simulations of aqueous solutions of N-methylacetamide using both nonpolarizable and polarizable force fields. Potassium and, more strongly, sodium exhibit an affinity for the carbonyl oxygen of the amide group, while none of the halide anions shows any appreciable attraction for the amide hydrogen. Heavier halides, however, interact with the hydrophobic methyl groups of N-methylacetamide. Using the present results for a model of the peptide bond we predict that the destabilizing effect of weakly hydrated Hofmeister ions, such as bromide or iodide, is not due to direct interactions with the backbone but rather due to attraction to hydrophobic regions of the protein.
References provided by Crossref.org
Anion-cation contrast of small molecule solvation in salt solutions
Weakly hydrated anions bind to polymers but not monomers in aqueous solutions
