Wheeler D L, Chrambach A
Section on Macromolecular Analysis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-0001.
Biopolymers. 1995 Feb;35(2):179-85. doi: 10.1002/bip.360350206.
The gel electrophoresis of DNA of identical length but various static conformations was simulated using a two-dimensional model of the movement of rod-shaped, arc-shaped, and circular objects through random arrays of disk-shaped obstacles. At low obstacle density, the displacement rate of these objects decreases from the rod-shaped to the circular to the arc-shaped objects. At high obstacle densities, the displacement rate of circular objects approaches zero. The alignment of the arc-shaped objects along the axis of the directional movement of the objects were retarded in their movement by collisions with the obstacles; the number of collisions of the former, in view of their greater ability to align, was less than that of the latter. Circular objects were exclusively retarded by collisions, while the arc-shaped objects exhibited an additional retarding mechanism, viz. the suspension ("hanging") on the obstacles. When the rigid objects were made flexible, their displacement increased. The increase was most pronounced with the circular objects, allowing them to penetrate at obstacle densities from which the rigid objects were excluded.
利用杆状、弧形和圆形物体在圆盘状障碍物随机阵列中移动的二维模型，模拟了长度相同但静态构象各异的DNA的凝胶电泳。在低障碍物密度下，这些物体的位移速率从杆状物体到圆形物体再到弧形物体逐渐降低。在高障碍物密度下，圆形物体的位移速率趋近于零。弧形物体沿物体定向移动轴的排列在与障碍物碰撞时其移动受到阻碍；鉴于前者更强的排列能力，其碰撞次数少于后者。圆形物体仅因碰撞而受阻，而弧形物体则表现出一种额外的阻碍机制，即悬挂在障碍物上。当刚性物体变得灵活时，它们的位移增加。这种增加在圆形物体中最为明显，使它们能够在刚性物体被排除的障碍物密度下穿透。
