English
Related papers

Related papers: Proteins analysed as virtual knots

200 papers

We introduce a notion of intrinsic linking and knotting for virtual spatial graphs. Our theory gives two filtrations of the set of all graphs, allowing us to measure, in a sense, how intrinsically linked or knotted a graph is; we show that…

Geometric Topology · Mathematics 2014-10-01 Thomas Fleming , Blake Mellor

In this note, I describe a formalism for treating knots as geometric spaces, and make an application to a simple statistical mechanics computation. The motivation for this study is the natural visual symmetry of the knot, and I describe how…

Statistical Mechanics · Physics 2013-07-04 Robert Kariotis

This manuscript introduces a new framework for the study of knots by exploring the neighborhood of knot embeddings in the space of simple open and closed curves in 3-space. The latter gives rise to a knotoid spectrum, which determines the…

Geometric Topology · Mathematics 2024-10-22 Eleni Panagiotou

Proteins are a matter of dual nature. As a physical object, a protein molecule is a folded chain of amino acids with multifarious biochemistry. But it is also an instantiation along an evolutionary trajectory determined by the function…

Biomolecules · Quantitative Biology 2019-09-04 Jean-Pierre Eckmann , Jacques Rougemont , Tsvi Tlusty

Protein molecules can be approximated by discrete polygonal chains of amino acids. Standard topological tools can be applied to the smoothening of the polygons to introduce a topological classification of proteins, for example, using the…

Biomolecules · Quantitative Biology 2019-03-12 Dmitry Melnikov , Antti J Niemi , Ara Sedrakyan

A major issue in biology is the understanding of the interactions between proteins. These interactions can be described by a network, where the proteins are modeled by nodes and the interactions by edges. The origin of these protein…

Biological Physics · Physics 2011-08-01 Christian M. Schneider , Lucilla de Arcangelis , Hans J. Herrmann

Virtual knot theory, introduced by Kauffman, is a generalization of classical knot theory of interest because its finite-type invariant theory is potentially a topological interpretation of Etingof and Kazhdan's theory of quantization of…

Geometric Topology · Mathematics 2012-09-21 Karene Chu

Virtual knots are defined diagrammatically as a collection of figures, called virtual knot diagrams, that are considered equivalent up to finite sequences of extended Reidemeister moves. By contrast, knots in $\mathbb{R}^3$ can be defined…

Geometric Topology · Mathematics 2023-01-26 Micah Chrisman

A commonly recurring problem in structural protein studies, is the determination of all heavy atom positions from the knowledge of the central alpha-carbon coordinates. We employ advances in virtual reality to address the problem. The…

Biomolecules · Quantitative Biology 2014-12-30 Xubiao Peng , Alireza Chenani , Shuangwei Hu , Yifan Zhou , Antti J. Niemi

Knots are fascinating topological structures that have been observed in various contexts, ranging from micro-worlds to macro-systems, and are conjectured to play a fundamental role in their respective fields. In order to characterize their…

Biological Physics · Physics 2021-10-27 Tian Chen , Xingen Zheng , Qingsong Pei , Deyuan Zou , Houjun Sun , Xiangdong Zhang

Knots across various length scales, from micro to macro-scales, such as polymers, DNA, shoelaces, and surgery, serving their unique mechanical properties. The shape of ideal knots has been extensively studied in the context of knot theory,…

Soft Condensed Matter · Physics 2025-07-01 Taiki Goto , Shunsuke Nomura , Tomohiko G. Sano

Advanced Monte Carlo simulations are used to study the effect of nano-slit confinement on metric and topological properties of model DNA chains. We consider both linear and circularised chains with contour lengths in the 1.2--4.8 $\mu$m…

Biological Physics · Physics 2012-04-11 C. Micheletti , E. Orlandini

We present a systematic classification of uncolored bonded knots with singularity number at most seven. Bonded knots provide a topological model for closed protein chains with intramolecular bridges, such as disulfide bonds. Following the…

Geometric Topology · Mathematics 2026-03-20 Boštjan Gabrovšek , Matic Simonič , Wanda Niemyska

Computational docking methods can provide structural models of protein-protein complexes, but protein backbone flexibility upon association often thwarts accurate predictions. In recent blind challenges, medium or high accuracy models were…

Biomolecules · Quantitative Biology 2020-12-29 Ameya Harmalkar , Jeffrey J. Gray

The protein folding problem must ultimately be solved on all length scales from the atomic up through a hierarchy of complicated structures. By analyzing the stability of the folding process using physics and mathematics, this paper shows…

Biological Physics · Physics 2015-05-28 Walter Simmons , Joel L. Weiner

The discovery of knotting in proteins and other macromolecular chains has motivated researchers to more carefully consider how to identify and classify knots in open arcs. Most definitions classify knotting in open arcs by constructing an…

The prediction of the three-dimensional native structure of proteins from the knowledge of their amino acid sequence, known as the protein folding problem, is one of the most important yet unsolved issues of modern science. Since the…

Biological Physics · Physics 2008-11-24 Pablo Echenique

DNA bending is biologically important for genome regulation and is relevant to a range of nanotechnological systems. Recent results suggest that sharp bending is much easier than implied by the widely-used worm-like chain model; many of…

Biomolecules · Quantitative Biology 2015-07-01 Ryan M. Harrison , Flavio Romano , Thomas E. Ouldridge , Ard A. Louis , Jonathan P. K. Doye

The amount and type of self-entanglement of DNA filaments is significantly affected by spatial confinement, which is ubiquitous in biological systems. Motivated by recent advancements in single DNA molecule experiments based on nanofluidic…

Soft Condensed Matter · Physics 2013-02-18 E. Orlandini , C. Micheletti

The most tight conformations of prime knots are found with the use of the SONO algorithm. Their curvature and torsion profiles are calculated. Symmetry of the knots is analysed. Connections with the physics of polymers are discussed.

Computational Physics · Physics 2009-11-07 P. Pieranski , S. Przybyl , A. Stasiak