Stigter D
Department of Pharmaceutical Chemistry, University of California, San Francisco 94143.
Biopolymers. 1991 Feb 5;31(2):169-76. doi: 10.1002/bip.360310205.
Results of free electrophoresis and free sedimentation of charged rods are introduced to allow for electrical double-layer effects in the gel electrophoresis of DNA, modeled as a random flight sequence of rodlike Kuhn chain elements. The kinetics of DNA is shown to depend strongly on the orientation of the chain elements with respect to the external field and with respect to the direction of their velocity. The new theory gives approximate agreement between the DNA charge derived from electrophoresis of free and tethered DNA (close to 1.0e per DNA phosphate in both cases), compared with the earlier discrepancy of a factor 10 or 20 for the theory without shielding by salt. As part of a realistic force field for macromolecular dynamics simulation, the small ion effects are included in an expression for the gel forces restraining the DNA in gel electrophoresis from moving as in free electrophoresis.
介绍了带电棒的自由电泳和自由沉降结果，以考虑DNA凝胶电泳中的电双层效应，DNA被建模为棒状库恩链元素的随机飞行序列。结果表明，DNA的动力学在很大程度上取决于链元素相对于外部场以及相对于其速度方向的取向。与早期未考虑盐屏蔽的理论相差10倍或20倍相比，新理论给出了从自由DNA和束缚DNA电泳得出的DNA电荷之间的近似一致性（两种情况下每个DNA磷酸基团接近1.0e）。作为大分子动力学模拟实际力场的一部分，小离子效应包含在凝胶力的表达式中，该表达式用于抑制凝胶电泳中的DNA像在自由电泳中那样移动。
