Structure and energy of a DNA dodecamer under tensile load
Structure and energy of a DNA dodecamer under tensile load
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拉伸载荷下 DNA 十二聚体的结构和能量
作者：
S. Piana
在过去的十年中，已经开发了在拉伸载荷下研究单个DNA分子的方法。这些实验测量拉伸和熔化双螺旋所需的力，并提供对DNA结构稳定性的见解。然而，不容易将力曲线的形状与拉伸载荷下双螺旋中发生的结构变化直接联系起来。在这里，国家的最先进的计算机模拟的短DNA序列进行提供一个原子的描述的DNA双螺旋的拉伸。这些计算表明，对于大于25%的延伸，DNA经历了结构转变，螺旋的末端和中心部分都丢失了一些碱基对。这种局部熔化的DNA双链体是稳定的，并且可以在恒定的力下延伸至平衡长度的50-60%。它的结论是，在张力下的熔化不能被建模为一个简单的两态过程。最后，讨论了悬臂刚度在确定力-延伸曲线形状和最可能的断裂力方面的重要作用。
In the last decade, methods to study single DNA molecules under tensile load have been developed. These experiments measure the force required to stretch and melt the double helix and provide insights into the structural stability of DNA. However, it is not easy to directly relate the shape of the force curve to the structural changes that occur in the double helix under tensile load. Here, state-of-the-art computer simulations of short DNA sequences are preformed to provide an atomistic description of the stretching of the DNA double helix. These calculations show that for extensions larger that ∼25% the DNA undergoes a structural transformation and a few base pairs are lost from both the terminal and central part of the helix. This locally melted DNA duplex is stable and can be extended up to ∼50–60% of the equilibrium length at a constant force. It is concluded that melting under tension cannot be modeled as a simple two-state process. Finally, the important role of the cantilever stiffness in determining the shape of the force–extension curve and the most probable rupture force is discussed.
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影响因子：
3.4
作者：
Williams, MC;Wenner, JR;Bloomfield, VA
通讯作者：
Bloomfield, VA
影响因子：
3.4
作者：
Rouzina, I;Bloomfield, VA
通讯作者：
Bloomfield, VA
影响因子：
3.4
作者：
Wenner, JR;Williams, MC;Bloomfield, VA
通讯作者：
Bloomfield, VA
DOI：
10.1073/pnas.83.11.3746
发表时间：
1986-06-01
影响因子：
11.1
作者：
BRESLAUER, KJ;FRANK, R;MARKY, LA
通讯作者：
MARKY, LA
影响因子：
3.4
作者：
Rouzina, I;Bloomfield, VA
通讯作者：
Bloomfield, VA