Sheardy R D, Winkle S A
Department of Chemistry, Pennsylvania State University, Hazleton 18201.
Biochemistry. 1989 Jan 24;28(2):720-5. doi: 10.1021/bi00428a046.
It is now accepted that two or more conformations may exist within the same DNA molecule, thereby generating conformational junctions. The presence of B-Z junctions between right- and left-handed DNA conformations has been detected in plasmids by a number of techniques. Preliminary characterization of the first example of a B-Z junction is a short DNA oligonucleotide has recently been reported [Sheardy, R. D. (1988) Nucleic Acids Res. 16, 1153-1167]. We report additional CD and NMR data that support the existence of the junction in this model oligomer. These studies indicate that only three base pairs are involved in the junction and only one of these is dramatically distorted. Furthermore, the NMR saturation-transfer experiments suggest the junction's internal motion is temperature dependent.
现在人们已经接受，同一DNA分子内可能存在两种或更多种构象，从而产生构象连接点。通过多种技术已在质粒中检测到右手和左手DNA构象之间存在B-Z连接点。最近有报道称，对首个B-Z连接点实例（一种短DNA寡核苷酸）进行了初步表征[谢迪，R. D.（1988年）《核酸研究》16卷，第1153 - 1167页]。我们报告了额外的圆二色光谱（CD）和核磁共振（NMR）数据，这些数据支持该模型寡聚物中连接点的存在。这些研究表明，连接点仅涉及三个碱基对，其中只有一个碱基对发生了显著扭曲。此外，核磁共振饱和转移实验表明，连接点的内部运动与温度有关。
