Jollès B, Chinsky L, Laigle A
Biochimie. 1984 Feb;66(2):101-4. doi: 10.1016/0300-9084(84)90196-2.
Resonance Raman Spectroscopy allows a selective study of the bases of DNA and therefore of the interactions of these bases with ligands. This technique is also sensitive to structural modifications. We show here that, first, the structures of native poly(dA-dT).poly(dA-dT) and poly(dA).poly(dT) are not the same and that, secondly, it is possible to characterize the B----Z transition of poly(dG-dC).poly(dG-dC). The study of the Raman hypochromism during the thermal denaturation of the polynucleotides reveals that the stacking of the adenines in poly(dA).poly(dT) is near that observed in poly(rA) but differs of this stacking in poly(dA-dT).poly(dA-dT). The enhancement of the intensity of the guanine line at 1193 cm-1 and of the cytosine lines at 780 cm-1, 1 242 cm-1 and 1268 cm-1 as well as the shift of the guanine line at low frequency should allow to characterize a small proportion of base pairs in Z form in any DNA.
共振拉曼光谱法能够对DNA的碱基进行选择性研究，进而研究这些碱基与配体之间的相互作用。该技术对结构修饰也很敏感。我们在此表明，首先，天然的聚（dA-dT）·聚（dA-dT）和聚（dA）·聚（dT）的结构并不相同，其次，有可能对聚（dG-dC）·聚（dG-dC）的B→Z转变进行表征。对多核苷酸热变性过程中拉曼减色现象的研究表明，聚（dA）·聚（dT）中腺嘌呤的堆积情况与聚（rA）中观察到的情况相近，但与聚（dA-dT）·聚（dA-dT）中的这种堆积不同。1193 cm-1处鸟嘌呤谱线以及780 cm-1、1242 cm-1和1268 cm-1处胞嘧啶谱线强度的增强，以及低频处鸟嘌呤谱线的位移，应有助于表征任何DNA中一小部分Z型碱基对。
