Conformational changes of peptides at solid/liquid interfaces: a Monte Carlo study.

Amol A Mungikar; Daniel Forciniti

doi:10.1021/bm049808s

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Conformational changes of peptides at solid/liquid interfaces: a Monte Carlo study.

Amol A Mungikar·Daniel Forciniti

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Abstract

Monte Carlo simulations were performed to study the conformational changes of negatively charged model peptides dissolved in water adsorbed onto charged surfaces. 8-, 16-, and 20-residues peptides were used, each of them consisted of repeating diblock units of aspartic acid (ASP, polar amino acid) and isoleucine (ILE, nonpolar amino acid) residues. We found that a water patch was retained at the charged surface, separating the peptide from it. We believed that these water molecules were primarily responsible for giving a particular orientation to the peptide at the surface. Water did play a role to some extent in the structural stability of the 8-residues peptide. However, for higher chain lengths (16-residues and 20-residues), the intrinsic hydrogen-bonding network (or intrinsic structural stability) showed a predominant effect over hydrophobic dehydration for the stability of the peptide at the surface.

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Adsorption Biophysical Phenomena Biophysics Hydrogen Bonding Macromolecular Substances Models, Molecular Models, Statistical Models, Theoretical Molecular Conformation Monte Carlo Method Oxygen Peptides Protein Conformation Static Electricity Water Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Amol A Mungikar, Daniel Forciniti. Conformational changes of peptides at solid/liquid interfaces: a Monte Carlo study.. https://doi.org/10.1021/bm049808s

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