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Interactive Molecular Model Assembly with 3D Printing
Published on: August 13, 2020
Entropic and enthalpic contributions to the chair-boat conformational transformation in dextran under single molecule
Richard G Haverkamp1, Aaron T Marshall, Martin A K Williams
1Institute of Technology and Engineering, Massey University, Private Bag 11222, Palmerston North, New Zealand. r.haverkamp@massey.ac.nz
Abstract:
The contribution of entropy and enthalpy to the chair-boat conformational changes (clicks) occurring during the force-extension of single molecules of an axially linked polysaccharide, dextran, was investigated. Experimental single molecule force-extension measurements were carried out by atomic force microscopy over the temperature range of 5-70 degrees C. This enabled the separation of the entropy and enthalpy components of the conformational change. The contribution of entropy to the Gibbs energy of the conformational transformation was found to be small (<12 J mol(-1) K(-1)), demonstrating that the click is largely (>89%) enthalpic in nature.
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