Entropically Driven Helix Formation

  title={Entropically Driven Helix Formation},
  author={Yehuda Snir and Randall D. Kamien},
  pages={1067 - 1067}
The helix is a ubiquitous motif for biopolymers. We propose a heuristic, entropically based model that predicts helix formation in a system of hard spheres and semiflexible tubes. We find that the entropy of the spheres is maximized when short stretches of the tube form a helix with a geometry close to that found in natural helices. Our model could be directly tested with wormlike micelles as the tubes, and the effect could be used to self-assemble supramolecular helices. 
Helix-like structure formation of a semi-flexible chain confined in a cylinder channel*
Molecular dynamics method is used to study the conformation behavior of a semi-flexible polymer chain confined in a cylinder channel. A novel helix-like structure is found to form during theExpand
Local coil–helix transition of semiflexible polymers confined in spheres
An off-lattice Monte Carlo method is used to study the conformations of semiflexible polymer chains confined in spheres. The local coil–helix transition is observed for the chains with moderateExpand
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It turns out that helical structures, strands, rings, and coils are natural, intrinsic geometries of such tubelike objects. Expand
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Molecular dynamics simulations demonstrate that several polyacetylene (PA) chains can encapsulate and self-assemble into multi-stranded helical structures in confined inner space of carbon nanotubesExpand
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The results of numerical simulations are presented in order to understand the role played by the finite length of short polymers and the discrete versus continuum descriptions of the system in determining the preferred conformation. Expand


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A framework is presented for understanding the common character of proteins. Proteins are linear chain molecules. However, the simple model of a polymer viewed as spheres tethered together does notExpand
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We develop theory to explore the relationship between the amino acid sequence of a protein and its native structure. A protein is modeled as a specific sequence of H (nonpolar) and P (polar)Expand
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