Shapes of semiflexible polymers in confined spaces.
نویسندگان
چکیده
Biological macromolecules, living in the confines of a cell, often adopt conformations that are unlikely to occur in free space. In this paper, we investigate the effects of confinement on the shape of a semiflexible chain. Results of Monte Carlo simulations show the existence of a shape transition when the persistence length of the polymer becomes comparable to the dimensions of the box. An order parameter is introduced to quantify this behavior. A simple model is constructed to study the effect of the shape transition on the effective persistence length of the polymer.
منابع مشابه
Some Rigorous Results on Semiflexible Polymers I. Free and confined polymers
We introduce a class of models of semiflexible polymers. The latter are characterized by a strong rigidity, the correlation length associated to the gradient-gradient correlations, called the persistence length, being of the same order as the polymer length. We determine the macroscopic scaling limit, from which we deduce bounds on the free energy of a polymer confined inside a narrow tube.
متن کاملBrownian dynamics simulations of charged semiflexible polymers confined to curved surfaces.
As an extension of the generalized bead-rod model developed earlier by the authors, this paper proposes a method for Brownian dynamics simulations of charged semiflexible polymers confined to various curved surfaces such as spherical, cylindrical, ellipsoidal and toroidal. We model charged semiflexible polymers as discrete wormlike chains consisting of virtual beads connected by inextensible ro...
متن کاملLongitudinal response of confined semiflexible polymers.
The longitudinal response of single semiflexible polymers to sudden changes in externally applied forces is known to be controlled by the propagation and relaxation of backbone tension. Under many experimental circumstances, realized, for example, in nanofluidic devices or in polymeric networks or solutions, these polymers are effectively confined in a channel- or tubelike geometry. By means of...
متن کاملConformations of entangled semiflexible polymers: entropic trapping and transient non-equilibrium distributions.
The tube model is a central concept in polymer physics, and allows one to reduce the complex many-filament problem of an entangled polymer solution to a single-filament description. We investigate the probability distribution function of conformations of confinement tubes and single encaged filaments in entangled semiflexible polymer solutions. Computer simulations are developed that mimic the ...
متن کاملOn the confinement of semiflexible chains under torsion.
The effect of a finite torque on semiflexible polymers in a confined environment is investigated. It is shown how a new length scale appears in the strongly confined limit. The influence of a torque on the extension of biopolymers in nanochannels is also touched upon and it is argued that the presence of a torque has a strong influence on the dimensions of nanochannels needed to prevent hairpins.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical biology
دوره 5 2 شماره
صفحات -
تاریخ انتشار 2008