Školáková Petra, Kejnovská Iva, Renčiuk Daniel
Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65, Brno, Czech Republic.
Eur Biophys J. 2025 Jun 12. doi: 10.1007/s00249-025-01767-7.
Nucleic acids, molecules essential for all life, can adopt many alternative structures besides the well-known right-handed double helix, some of which have been reported to exist and function in vivo. One of the most appropriate methods for structural studies of nucleic acids is circular dichroism spectroscopy, utilizing structure-induced chirality due to the asymmetric winding of absorbing nucleobases. Using electronic CD and absorption spectroscopies in combination with melting experiments, we analyzed a conformational equilibrium between DNA double helix and two alternative conformations of nucleic acids, cytosine i-motifs and guanine quadruplexes, as a function of the primary structure of model G/C-rich sequences, containing blocks of G and C runs in particular DNA strands. This paper is a part of special issue dedicated to 70th anniversary of the Biophysical Institute of the Czech Academy of Sciences, where circular dichroism spectroscopy of nucleic acids has been used successfully and impactfully for many years.
核酸是所有生命所必需的分子，除了众所周知的右手双螺旋结构外，还可以呈现许多其他结构，其中一些已被报道在体内存在并发挥作用。圆二色光谱法是核酸结构研究最合适的方法之一，它利用由于吸收性核碱基的不对称缠绕而产生的结构诱导手性。我们结合电子圆二色光谱和吸收光谱以及熔解实验，分析了DNA双螺旋与核酸的两种替代构象（胞嘧啶i-基序和鸟嘌呤四链体）之间的构象平衡，该平衡是富含G/C的模型序列一级结构的函数，这些序列在特定DNA链中包含G和C连续片段。本文是献给捷克科学院生物物理研究所成立70周年特刊的一部分，多年来，核酸的圆二色光谱法在这里得到了成功且有效的应用。
