Writhing Geometry of Open DNA

Abstract

Motivated by recent experiments on DNA torsion-force-extension characteristics we consider the writhing geometry of open stiff molecules. We exhibit a cyclic motion which allows arbitrarily large twisting of the end of a molecule via an activated process. This process is suppressed for forces larger than femto-Newtons which allows us to show that experiments are sensitive to a generalization of the Calugareanu-White formula for the writhe. Using numerical methods we compare this formulation of the writhe with recent analytic calculations.

12 pages 10 figures. Revtex4

References in corpus (5)

• Elasticity model of a supercoiled DNA molecule
• Entropic Elasticity of Twist-Storing Polymers
• Critical exponents for random knots
• Writhing Geometry at Finite Temperature: Random Walks and Geometric phases for Stiff Polymers
• Comment on "Elasticity Model of a Supercoiled DNA Molecule"

Cited by in corpus (9)

• Getting DNA twist rigidity from single molecule experiments
• Elasticity and electrostatics of plectonemic DNA
• Stretching helical nano-springs at finite temperature
• Writhe formulas and antipodal points in plectonemic DNA configurations
• DNA Elasticity : Topology of Self-Avoidance
• Observation of a non-adiabatic geometric phase for elastic waves
• DNA loop statistics and torsional modulus
• A symplectic integration method for elastic filaments
• A consistent treatment of link and writhe for open rods, and their relation to end rotation