Phenomenological modeling of DNA overstretching
نویسندگان
چکیده
A phenomenological model based on the three-dimensional theory of nonlinear elasticity is developed to describe the phenomenon of overstretching in the force-extension curve for dsDNA. By using the concept of a material with multiple reference configurations a single formula is obtained to fit the force-extension curve.
منابع مشابه
DNA overstretching transition induced by melting in a dynamical mesoscopic model.
We present a phenomenological dynamical model describing the force induced melting as responsible for the DNA overstretching transition. The denaturation mechanism is developed under the framework of the mesoscopic one-dimensional Peyrard-Bishop-Dauxois (PBD) picture which models the melting features of a polymer chain by means of a Morse potential and the stacking interaction. We find a good a...
متن کاملMechanism of Threshold Elongation of DNA Macromolecule
The mechanism of threshold elongation (overstretching) of DNA macromolecules under the action of external force is studied within the framework of phenomenological approach. When considering the task it is taken into account that double-stranded DNA is a polymorphic macromolecule with a set of metastable states. Accordingly to proposed mechanism, DNA threshold elongation can take place as a coo...
متن کاملCoarse-grained simulations of DNA overstretching.
We use a recently developed coarse-grained model to simulate the overstretching of duplex DNA. Overstretching at 23 °C occurs at 74 pN in the model, about 6-7 pN higher than the experimental value at equivalent salt conditions. Furthermore, the model reproduces the temperature dependence of the overstretching force well. The mechanism of overstretching is always force-induced melting by unpeeli...
متن کاملDynamical model for the full stretching curve of DNA.
We present a phenomenological dynamical model able to describe the stretching features of the curve of DNA length vs applied force. As concerns the chain, the model is based on the discrete wormlike chain model with elastic modifications, which properly describes the elongation features at low and intermediate forces. The dynamics is developed under a double-well potential with a linear term, w...
متن کاملTransition dynamics and selection of the distinct S-DNA and strand unpeeling modes of double helix overstretching
Recent studies have revealed two distinct pathways for the DNA overstretching transition near 65 pN: 'unpeeling' of one strand from the other, and a transition from B-DNA to an elongated double-stranded 'S-DNA' form. However, basic questions concerning the dynamics of these transitions, relative stability of the two competing overstretched states, and effects of nicks and free DNA ends on overs...
متن کامل