Premilat S, Harmouchi M, Albiser G
Laboratoire de Biophysique Moléculaire, U.A. CNRS 494, Faculté des Sciences, Université de Nancy, Vandoeuvre les Nancy, France.
Biophys Chem. 1990 Jan;35(1):37-45. doi: 10.1016/0301-4622(90)80058-f.
The method proposed for the study of DNA conformational transitions is based on the proportionality, experimentally observed, between the length of a DNA fiber and the axial rise per nucleotide characterizing the molecular helix. Precise curves for the A-B and B-C transitions as a function of the relative humidity are obtained by using X-ray fiber data and measurements of fiber dimensions. It is thus shown that the A-B transition is a cooperative process between two different states, whereas the B-C transition can be considered as a progressive change of conformation. The present method is applied on two natural DNAs differing in base composition so that the effect of the nucleotide content on the conformational changes can be estimated.
所提出的用于研究DNA构象转变的方法基于实验观察到的DNA纤维长度与表征分子螺旋的每个核苷酸的轴向上升之间的比例关系。通过使用X射线纤维数据和纤维尺寸测量，获得了作为相对湿度函数的A - B和B - C转变的精确曲线。结果表明，A - B转变是两种不同状态之间的协同过程，而B - C转变可被视为构象的渐进变化。本方法应用于两种碱基组成不同的天然DNA，从而可以估计核苷酸含量对构象变化的影响。
