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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Thermal stability of the secondary structure of poly(alpha,L-glutamate) in self-assembled complexes as studied by
David Zanuy1, Jordi Casanovas, Carlos Alemán
1Laboratory of Experimental and Computational Biology, NCI-Frederick, Building 469, Room 151, Frederick, Maryland 21702, USA. zanuyd@ncifcrf.gov
Abstract:
The thermal stability of the self-assembled complexes formed by alkyltrimethylammonium surfactants and poly(alpha,l-glutamate) is investigated in dilute chloroform solution by molecular dynamics simulations. By applying temperatures ranging from 300 to 500 K, we observed an extraordinary stability of the alpha-helix adopted by the polypeptide during a total of 48 ns. The multiple electrostatic interactions formed between the surfactant chains and the polyanion play a crucial role in this stability since they are responsible for the inaccessibility of the solvent molecules to the helix even at high temperatures.
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