Rozners Eriks
Binghamton University, The State University of New York, Binghamton, New York, USA.
Curr Protoc Nucleic Acid Chem. 2010 Dec;Chapter 7:Unit 7.14. doi: 10.1002/0471142700.nc0714s43.
Water plays an important role in structure and molecular recognition of biopolymers. Understanding hydration of biopolymers is a significant problem in structural chemistry and biology. However, hydration is a dynamic process that is difficult to study. While X-ray crystallography, NMR, and molecular modeling have provided structural detail on nucleic acid hydration and valuable insights into water dynamics, the thermodynamic contribution of water molecules to conformational equilibria and recognition of nucleic acids remains poorly understood. This unit describes a thermodynamic analysis of nucleic acid hydration using osmotic stress. Osmotic stress monitors the depression of melting temperature upon decreasing water activity, and calculates the number of thermodynamically unique water molecules associated with the double helix and released from single strands upon melting. Comparison of the number of water molecules released upon melting of nucleic acids with different sequences and chemical modifications provides insights that complement and enhance information obtained by other methods.
水在生物聚合物的结构和分子识别中起着重要作用。理解生物聚合物的水合作用是结构化学和生物学中的一个重大问题。然而，水合作用是一个难以研究的动态过程。虽然X射线晶体学、核磁共振和分子建模已经提供了核酸水合作用的结构细节以及对水动力学的宝贵见解，但水分子对核酸构象平衡和识别的热力学贡献仍然知之甚少。本单元描述了一种使用渗透压对核酸水合作用进行的热力学分析。渗透压监测水活性降低时熔解温度的下降，并计算与双螺旋相关且在熔解时从单链释放的热力学上独特的水分子数量。比较不同序列和化学修饰的核酸熔解时释放的水分子数量，可提供补充并增强通过其他方法获得的信息的见解。
