Book•
Statistical mechanics of chain molecules
01 Jan 1969-
About: The article was published on 1969-01-01 and is currently open access. It has received 4347 citations till now. The article focuses on the topics: Worm-like chain & Statistical mechanics.
Citations
More filters
TL;DR: In this article, an extensive molecular-dynamics simulation for a bead spring model of a melt of linear polymers is presented, where the number of monomers N covers the range from N=5 to N=400.
Abstract: We present an extensive molecular‐dynamics simulation for a bead spring model of a melt of linear polymers. The number of monomers N covers the range from N=5 to N=400. Since the entanglement length Ne is found to be approximately 35, our chains cover the crossover from the nonentangled to the entangled regime. The Rouse model provides an excellent description for short chains N
3,232 citations
TL;DR: In this paper, a review discusses the various attempts reported on solving this problem from the point of view of the chemistry and the structure of these polymers highlighting the drawbacks and advantages of each method and proposes that based on considerations of structure-property relations, it is possible to obtain chitin fibers with improved strength by making use of their nanostructures and/or mesophase properties of chitins.
2,278 citations
TL;DR: The energy landscape theory of protein folding suggests that the most realistic model of a protein is a minimally frustrated heteropolymer with a rugged funnel-like landscape biased toward the native structure.
Abstract: ▪ Abstract The energy landscape theory of protein folding is a statistical description of a protein's potential surface. It assumes that folding occurs through organizing an ensemble of structures rather than through only a few uniquely defined structural intermediates. It suggests that the most realistic model of a protein is a minimally frustrated heteropolymer with a rugged funnel-like landscape biased toward the native structure. This statistical description has been developed using tools from the statistical mechanics of disordered systems, polymers, and phase transitions of finite systems. We review here its analytical background and contrast the phenomena in homopolymers, random heteropolymers, and protein-like heteropolymers that are kinetically and thermodynamically capable of folding. The connection between these statistical concepts and the results of minimalist models used in computer simulations is discussed. The review concludes with a brief discussion of how the theory helps in the interpre...
2,040 citations
TL;DR: Deviations from the force curves predicted by the freely jointed chain model suggest that DNA has significant local curvature in solution, and the effect of bend-inducing cis-diamminedichloroplatinum (II) was large and supports the hypothesis of natural curvatures in DNA.
Abstract: Single DNA molecules were chemically attached by one end to a glass surface and by their other end to a magnetic bead. Equilibrium positions of the beads were observed in an optical microscope while the beads were acted on by known magnetic and hydrodynamic forces. Extension versus force curves were obtained for individual DNA molecules at three different salt concentrations with forces between 10(-14) and 10(-11) newtons. Deviations from the force curves predicted by the freely jointed chain model suggest that DNA has significant local curvature in solution. Ethidium bromide and 4',6-diamidino-2-phenylindole had little effect on the elastic response of the molecules, but their extent of intercalation was directly measured. Conversely, the effect of bend-inducing cis-diamminedichloroplatinum (II) was large and supports the hypothesis of natural curvature in DNA.
1,826 citations
TL;DR: In this paper, the authors investigated the application of the computer simulation method of molecular dynamics to macromolecules and compared different algorithms for integrating the equations of motion, both theoretically and in practice.
Abstract: The application of the computer simulation method of molecular dynamics to macromolecules is investigated. The protein trypsin inhibitor (BPTI), consisting of 454 united atoms, is used as an example. Different algorithms for integrating the equations of motion are compared, both theoretically and in practice. It is examined to what extent the chain structure of a macromolecule allows a reduction of the computational effort by the introduction of constraints in the dynamics of the chain. A calculational scheme is proposed, by which constraints can be incorporated in predictor-corrector algorithms. The optimum choice of an algorithm depends on the desired accuracy of the solution and on the character of the forces acting on the molecule, viz. whether these are noisy or not. For nonconstraint dynamics a Gear predictor-corrector algorithm yields the best results, whereas for constraint dynamics the Gear and Verlet algorithms produce comparable results. The application of bond-length constraints reduces the re...
1,589 citations