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Related papers: Discontinuities at the DNA supercoiling transition

200 papers

Double-stranded DNA `overstretches' at a pulling force of about 65 pN, increasing in length by a factor of 1.7. The nature of the overstretched state is unknown, despite its considerable importance for DNA's biological function and…

Statistical Mechanics · Physics 2009-11-13 Stephen Whitelam , Sander Pronk , Phillip L. Geissler

We examine the conformations of a model for under- and overwound DNA. The molecule is represented as a cylindrically symmetric elastic string subjected to a stretching force and to constraints corresponding to a specification of the link…

Soft Condensed Matter · Physics 2009-10-28 Boris Fain , Joseph Rudnick , Stellan Ostlund

DNA supercoiling plays an important role in a variety of cellular processes. The torsional stress related with supercoiling may be also involved in gene regulation through the local structure and dynamics of the double helix. To check this…

Biomolecules · Quantitative Biology 2015-05-19 Alexey K. Mazur

Structural changes in giant DNA induced by the addition of the flexible polymer PEG were examined by the method of single-DNA observation. In dilute DNA conditions, individual DNA assumes a compact state via a discrete coil-globule…

Soft Condensed Matter · Physics 2016-08-31 M. Kojima , K. Kuobo , K. Yoshikawa

We show that a mesoscale model, with a minimal number of parameters, can well describe the thermomechanical and mechanochemical behavior of homogeneous DNA at thermal equilibrium under tension and torque. We predict critical temperatures…

Biomolecules · Quantitative Biology 2015-06-22 Cristiano Nisoli , A. R. Bishop

The percentage and sequence of AT and GC base pairs and charges on the DNA backbone contribute significantly to the stiffness of DNA. This elastic property of DNA also changes with small interacting ligands. The single-molecule force…

Soft Condensed Matter · Physics 2017-02-02 Anurag Singh , Amar Nath Gupta

DNA is increasingly employed for bio and nanotechnology thanks to its exquisite versatility and designability. Most of its use is limited to linearised and torsionally relaxed DNA but non-trivial architectures and torsionally constrained --…

Soft Condensed Matter · Physics 2020-09-22 Jan Smrek , Davide Michieletto

This paper aims at a comprehensive understanding on the novel elastic property of double-stranded DNA (dsDNA) discovered very recently through single-molecule manipulation techniques. A general elastic model for double-stranded biopolymers…

Soft Condensed Matter · Physics 2009-10-31 Haijun Zhou , Yang Zhang , Zhong-can Ou-Yang

The transport of DNA polymers through nanoscale pores is central to many biological processes, from bacterial gene exchange to viral infection. In single-molecule nanopore sensing, the detection of nucleic acid and protein analytes relies…

The genomic DNA of most bacteria is significantly underwound, which constrains the DNA molecule to adopt a branched plectoneme geometry. Moreover, biological functions like replication and transcription require that the two DNA strands be…

Biological Physics · Physics 2025-11-04 Marc Joyeux

DNA supercoiling is central to many fundamental processes of living organisms. Its average level along the chromosome and over time reflects the dynamic equilibrium of opposite activities of topoisomerases, which are required to relax…

Biomolecules · Quantitative Biology 2023-10-09 Ivan Junier , Elham Ghobadpour , Olivier Espeli , Ralf Everaers

We propose that supercoiling energizes double-stranded DNA (dsDNA) so as to facilitate thermal fluctuations to an unzipped state. We support this with a model of two elastic rods coupled via forces that represent base pair interactions.…

Soft Condensed Matter · Physics 2009-11-10 Shirish M. Chitanvis , Paul M. Welch

We calculate the equation of state of DNA under tension for the case that the DNA features loops. Such loops occur transiently during DNA condensation in the presence of multivalent ions or sliding cationic protein linkers. The…

Biomolecules · Quantitative Biology 2007-05-23 I. M. Kulic , H. Mohrbach , R. Thaokar , H. Schiessel

Biological information is not only stored in the digital chemical sequence of double helical DNA, but is also encoded in the mechanical properties of the DNA strands, which can influence biochemical processes involving its readout. For…

Soft Condensed Matter · Physics 2015-06-10 Christian Matek , Thomas E. Ouldridge , Jonathan P. K. Doye , Ard A. Louis

Braids composed of two interwoven polymer chains exhibit a buckling transition whose origin has been explained through the onset of plectonemic structures. Here we study, by a combination of simulation and analytics, the dynamics of…

Soft Condensed Matter · Physics 2019-05-15 Giada Forte , Michele Caraglio , Davide Marenduzzo , Enzo Orlandini

We derive the single molecule equation of state (force-extension relation) for DNA molecules bearing sliding loops and deflection defects. Analytical results are obtained in the large force limit by employing an analogy with instantons in…

Soft Condensed Matter · Physics 2009-11-11 Igor M. Kulic , H. Mohrbach , V. Lobaskin , R. Thaokar , H. Schiessel

The study of configurational parameters of deformed DNA is a relevant problem in research of such important biological process as double helix compactization in cell. The deformations accompanied with local disruptions of the regular…

Biological Physics · Physics 2014-10-21 Kyrylo Simonov , Sergey N. Volkov

Chain-like macromolecules in solution, whether biological or synthetic, transform from a spatially extended conformation to a compact one upon change of temperature or solvent qualities. This sharp transition plays a key role in various…

Soft Condensed Matter · Physics 2007-05-23 H. Diamant , D. Andelman

The double-helical structure of DNA results from canonical base pairing and stacking interactions. However, variations from steady-state conformations result from mechanical perturbations in cells. These different topologies have…

Biomolecules · Quantitative Biology 2019-04-05 Jack W Shepherd , Robert J Greenall , Matt I J Probert , Agnes Noy , Mark C Leake

We reinvestigate the model originally studied by Neukirch and Marko that describes the extension, torque and supercoiling in single, stretched and twisted DNA molecules, which consists of a mixture of extended and supercoiled state, using…

Soft Condensed Matter · Physics 2016-06-02 Pui-Man Lam , Yi Zhen