title: Structural Basis for Elastic Mechanical Properties of the DNA Double Helix.
abstract: In this article, we investigate the principal structural features of the DNA double helix and their effects on its elastic mechanical properties. We develop, in the pursuit of this purpose, a helical continuum model consisting of a soft helical core and two stiff ribbons wrapping around it. The proposed model can reproduce the negative twist-stretch coupling of the helix successfully as well as its global stretching, bending, and torsional rigidities measured experimentally. Our parametric study of the model using the finite element method further reveals that the stiffness of phosphate backbones is a crucial factor for the counterintuitive overwinding behavior of the duplex and its extraordinarily high torsional rigidity, the major-minor grooves augment the twist-stretch coupling, and the change of the helicity might be responsible for the transition from a negative to a positive twist-stretching coupling when a tensile force is applied to the duplex.
authors.affiliation: Department of Mechanical and Aerospace Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Young-Joo
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Mechanical and Aerospace Engineering, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08826, Republic of Korea.|Institute of Advanced Machines and Design, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Do-Nyun
authors.initials: DN
authors.lastname: Kim
mesh_terms: D001696:Biomechanical Phenomena; D004247:DNA / Q000737:chemistry*; D004548:Elasticity; D020342:Finite Element Analysis; D006801:Humans; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D009690:Nucleic Acid Conformation
chemical_list: D004247:DNA