Mazur Alexey K
CNRS UPR9080, Institut de Biologie Physico-Chimique, 13, rue Pierre et Marie Curie, Paris, France.
Chemphyschem. 2008 Dec 22;9(18):2691-4. doi: 10.1002/cphc.200800446.
In recent years, significant progress has been made towards uncovering the physical mechanisms of low-hydration polymorphism in double-helical DNA. The effect appears to be mechanistically similar in different biological systems, and it is due to the ability of water to form spanning H-bonded networks around biomacromolecules via a quasi-two-dimensional percolation transition. In the case of DNA, disintegration of the spanning H-bonded network leads to electrostatic condensation of DNA strands because, below the percolation threshold, water loses its high dielectric permittivity, whereas the concentration of neutralizing counterions becomes high. In this Concept article arguments propose that this simple electrostatic mechanism represents the universal origin of low-hydration polymorphism in DNA.
近年来，在揭示双螺旋DNA低水合多态性的物理机制方面取得了重大进展。在不同的生物系统中，这种效应在机制上似乎是相似的，这是由于水能够通过准二维渗流转变在生物大分子周围形成跨越氢键的网络。就DNA而言，跨越氢键网络的解体导致DNA链的静电凝聚，因为在渗流阈值以下，水失去了高介电常数，而中和反离子的浓度变得很高。在这篇概念文章中，有观点认为这种简单的静电机制代表了DNA低水合多态性的普遍起源。
