New Molecular Mechanism of Dextran Extension in Single Molecule AFM

  • Igor Neelov
  • David Adolf
  • Tom McLeish
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3980)


A dextran monomer and a 10mer under constant pulling speed or constant force were studied using the atomistic simulations. Molecular dynamics (MD) with the Amber94 and Amber-Glycam04 forcefields were performed. The main result of the present Amber-based MD simulations is that the experimental plateau of the force-extension dependence for dextran can be explained by a transition of the glucopyranose rings in the dextran monomers from a chair (4C1) to a inverted chair (1C4) conformation whereas chair to boat transitions occur at higher forces. MD simulation of coarse-grained model of dextran consisting of two- or three-state monomers were performed to clarify the molecular mechanism of dextran extension.


Contour Length Boat Conformation C5C6 Bond Carbohydrate Research Monomer Length 
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© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Igor Neelov
    • 1
    • 2
  • David Adolf
    • 1
  • Tom McLeish
    • 1
  1. 1.IRC in Polymer Science and TechnologyUniversity of LeedsLeedsUK
  2. 2.Institute of Macromolecular Compounds, RASSt.PetersburgRussia

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