Chary K V, Modi S
Chemical Physics Group, Tata Institute of Fundamental Research, Bombay, India.
FEBS Lett. 1988 Jun 20;233(2):319-25. doi: 10.1016/0014-5793(88)80451-4.
A systematic analysis of the conformation of deoxyribofuranose rings in DNA fragments has been described using two-dimensional nuclear Overhauser effect spectroscopy (2D NOESY). The approach is based on the interpretation of the intrasugar proton-proton distances which can be estimated using a low-mixing-time pure-absorption mode w1-scaled NOESY spectrum. The experimental distances are compared with the theoretical values calculated as a function of pseudorotation phase angle (P) describing the sugar geometries. The approach can be used as a complementary aid to J couplings for establishing sugar conformations in individual nucleotide units of DNA fragments. Using this strategy on d-ACATCGATGT, we observed that individual nucleotides exhibit O4'-endo sugar pucker. The results rule out possibilities of the existence of a fast equilibrium (on the NMR time scale) between C2'-endo (or S-domain) and C3'-endo (or N-domain) sugar puckers.
已利用二维核Overhauser效应光谱法（2D NOESY）对DNA片段中脱氧呋喃核糖环的构象进行了系统分析。该方法基于对糖内质子-质子距离的解释，这些距离可通过低混合时间纯吸收模式w1缩放的NOESY光谱进行估算。将实验距离与作为描述糖几何形状的假旋转相角（P）的函数计算出的理论值进行比较。该方法可作为用于确定DNA片段单个核苷酸单元中糖构象的J耦合的补充辅助手段。对d-ACATCGATGT应用此策略时，我们观察到单个核苷酸呈现O4'-内型糖折叠。结果排除了在C2'-内型（或S结构域）和C3'-内型（或N结构域）糖折叠之间存在快速平衡（在NMR时间尺度上）的可能性。
