Benevides J M, Thomas G J
Nucleic Acids Res. 1983 Aug 25;11(16):5747-61. doi: 10.1093/nar/11.16.5747.
Raman spectra of poly(dG-dC) . poly(dG-dC) in D2O solutions of high (4.0M NaCl) and low-salt (0.1M NaCl) exhibit differences due to different nucleotide conformations and secondary structures of Z and B-DNA. Characteristic carbonyl modes in the 1600-1700 cm-1 region also reflect differences in base pair hydrogen bonding of the respective GC complexes. Comparison with A-DNA confirms the uniqueness of C = O stretching frequencies in each of the three DNA secondary structures. Most useful for qualitative identification of B, Z and A-DNA structures are the intense Raman lines of the phosphodiester backbone in the 750-850 cm-1 region. A conformation-sensitive guanine mode, which yields Raman lines near 682, 668, or 625 cm-1 in B (C2'-endo, anti), A (C3'-endo, anti) or Z (C3'-endo, syn) structures, respectively, is the most useful for quantitative analysis. In D2O, the guanine line of Z-DNA is shifted to 615 cm-1, permitting its detection even in the presence of proteins.
聚（dG-dC）·聚（dG-dC）在高盐（4.0M NaCl）和低盐（0.1M NaCl）的重水溶液中的拉曼光谱，由于Z-DNA和B-DNA不同的核苷酸构象和二级结构而呈现出差异。1600 - 1700 cm⁻¹区域的特征羰基模式也反映了各自GC复合物碱基对氢键的差异。与A-DNA的比较证实了三种DNA二级结构中C = O伸缩频率的独特性。750 - 850 cm⁻¹区域磷酸二酯主链的强拉曼线对于定性鉴定B、Z和A-DNA结构最为有用。一种构象敏感的鸟嘌呤模式，在B（C2'-内型，反式）、A（C3'-内型，反式）或Z（C3'-内型，顺式）结构中分别在682、668或625 cm⁻¹附近产生拉曼线，对定量分析最为有用。在重水中，Z-DNA的鸟嘌呤线移至615 cm⁻¹，即使在有蛋白质存在的情况下也能检测到它。
