By a News Reporter-Staff News Editor at Life Science Weekly -- Investigators discuss new findings in Amino Acids. According to news originating from Warsaw, Poland, by NewsRx correspondents, research stated, "The growing usage of nanoparticles of zinc sulfide as quantum dots and biosensors calls for a theoretical assessment of interactions of ZnS with biomolecules. We employ the molecular-dynamics-based umbrella sampling method to determine potentials of mean force for 20 single amino acids near the ZnS (110) surface in aqueous solutions."
Our news journalists obtained a quote from the research from the Institute of Physics, "We find that five amino acids do not bind at all and the binding energy of the remaining amino acids does not exceed 4.3 kJ/mol. Such energies are comparable to those found for ZnO (and to hydrogen bonds in proteins) but the nature of the specificity is different. Cysteine can bind with ZnS in a covalent way, e. g., by forming the disulfide bond with S in the solid. If this effect is included within a model incorporating the Morse potential, then the potential well becomes much deeper-the binding energy is close to 98 kJ/mol. We then consider tryptophan cage, a protein of 20 residues, and characterize its events of adsorption to ZnS. We demonstrate the relevance of interactions between the amino acids in the selection of optimal adsorbed conformations and recognize the key role of cysteine in generation of lasting adsorption. We show that ZnS is more hydrophobic than ZnO and that the density profile of water is quite different than that forming near ZnO-it has only a minor articulation into layers."
According to the news editors, the research concluded: "Furthermore, the first layer of water is disordered and mobile."
For more information on this research see: Interactions of aqueous amino acids and proteins with the (110) surface of ZnS in molecular dynamics simulations. Journal of Chemical Physics, 2014;140(9):392-402. Journal of Chemical Physics can be contacted at: Amer Inst Physics, Circulation & Fulfillment Div, 2 Huntington Quadrangle, Ste 1 N O 1, Melville, NY 11747-4501, USA. (American Institute of Physics - www.aip.org/; Journal of Chemical Physics - jcp.aip.org/)
The news correspondents report that additional information may be obtained from G. Nawrocki, Polish Academy Sci, Inst Phys, PL-02668 Warsaw, Poland (see also Amino Acids).
Keywords for this news article include: Warsaw, Poland, Europe, Physics, Peptides, Proteins, Amino Acids, Molecular Dynamics
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