Kumar M R, Hosur R V, Roy K B, Miles H T, Govil G
Biochemistry. 1985 Dec 17;24(26):7703-11. doi: 10.1021/bi00347a030.
Resonance assignments of nonexchangeable base and sugar protons of the self-complementary dodecanucleotide d-GGATCCGGATCC have been obtained by two-dimensional NMR methods and strategies derived from interproton distance calculations on different secondary structures of nucleic acids. Conformational details about the glycosidic dihedral angle and sugar pucker have been derived from the relative intensities of cross peaks in the two-dimensional J-correlated and nuclear Overhauser enhancement correlated spectra in D2O solution. It is observed that d-GGATCCGGATCC assumes a predominantly B-type conformation with sequence-dependent changes along the chain. The recognition site of BamHI shows a distinctly different geometrical environment. The sugar rings of G1 and G7 assume a C3'-endo geometry while the rest of the sugars possess C2'-endo geometry.
通过二维核磁共振方法以及基于核酸不同二级结构的质子间距离计算得出的策略，已获得了自互补十二聚体核苷酸d-GGATCCGGATCC中不可交换碱基和糖质子的共振归属。糖苷二面角和糖环构象的详细信息源自D2O溶液中二维J相关谱和核Overhauser增强相关谱交叉峰的相对强度。观察到d-GGATCCGGATCC主要呈现B型构象，且沿链存在序列依赖性变化。BamHI的识别位点显示出明显不同的几何环境。G1和G7的糖环呈现C3'-内向构象，而其余糖则具有C2'-内向构象。
