Abstrakt: |
The dynamics of conformational distortions in DNA has been studied in the framework of the simple mathematical model based on the sine-Gordon equation with two additional terms. The first of the terms describes the effects of dissipation, and the second takes the action of external field into account. With the help of the energetic method, an analytical expression for the velocity of local conformational distortion as a function of time has been found, and conditions have been determined under which the influence of dissipation and constant external force are in a balance, providing the distortion to move with a constant velocity along the DNA. The graphs of changes in the velocity of movement of local conformational distortions in different homogeneous polynucleotide chains have been constructed using the model values of the parameters v0 = 189 (m/s), beta(DNA) = 4.25 x 10(-34) (J x s) and F0(DNA) = 3.12 x 10(-22) (J), which determine the initial velocity of the distortion, the coefficient of dissipation, and the value of the external generalized force, respectively. The accordance of the model values used with the experimental values available from the literature is discussed. |