Chen Y Z, Prohofsky E W
Department of Physics, Purdue University, West Lafayette, IN 47907.
Nucleic Acids Res. 1992 Feb 11;20(3):415-9. doi: 10.1093/nar/20.3.415.
Experimental estimates of the premelting Adenine-Thymine base pair opening probability for some B-DNA sequences are two orders of magnitude smaller than those of other B-DNA sequences. The AT pairs in the sequence with smaller open probability seem to be those that have a well defined spine of hydration in the minor groove. We show that this spine of hydration can significantly enhance the thermal stability of the base pairs to which they are attached. The effect of this spine of hydration coupled with the possible stabilization effect contributed from neighboring GC pairs can explain the differences in the observed AT pair opening probability for different AT containing B-DNA sequences.
一些B-DNA序列的腺嘌呤-胸腺嘧啶碱基对预熔解开放概率的实验估计值比其他B-DNA序列的小两个数量级。开放概率较小的序列中的AT碱基对似乎是那些在小沟中有明确水合骨架的碱基对。我们表明,这种水合骨架可以显著提高与其相连的碱基对的热稳定性。这种水合骨架的作用,再加上相邻GC碱基对可能产生的稳定作用,可以解释不同含AT的B-DNA序列中观察到的AT碱基对开放概率的差异。