2017/09/30 by Panayotis Benetatos
Biochemistry, Genetics and Molecular Biology · Engineering · Physics and Astronomy · #Bending #Cellular Mechanics and Interactions #Composite material #Elasticity (physics) #Engineering #Flexural rigidity #Force Microscopy Techniques and Applications #Hinge #Materials science #Microfluidic and Bio-sensing Technologies #Protein filament #Rigidity (electromagnetism) #Structural engineering #Ultimate tensile strength #cond-mat.soft #cond-mat.stat-mech #physics.bio-ph
paper · pdf · doi:10.1103/physreve.96.042502
published as Phys. Rev. E 96, 042502 (2017) · revised version, accepted for publication in Physical Review E (11 pages, 7 figures)
arxiv created 2017/10/11 · openalex publication_date 2017/10/24 · arxiv updated 2017/11/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
It has become clear in recent years that the simple uniform wormlike chain model needs to be modified in order to account for more complex behavior which has been observed experimentally in some important biopolymers. For example, the large flexibility of short ds-DNA has been attributed to kink or hinge defects. In this paper, we calculate analytically, within the weak bending approximation, the force-extension relation of a wormlike chain with a permanent hinge defect along its contour. The defect is characterized by its bending energy (which can be zero, in the completely flexible case) and its position along the polymer contour. Besides the bending rigidity of the chain, these are the only parameters which describe our model. We show that a hinge defect causes a significant increase in the differential tensile compliance of a prestressed chain. In the small force limit, a hinge defect significantly increases the entropic elasticity. Our results apply to any pair of semiflexible segments connected by a hinge. As such, they may also be relevant to cytoskeletal filaments (F-actin, microtubules), where one may treat the cross-link connecting two filaments as a hinge defect.