MULTINUCLEAR NMR STUDIES OF CATION-DNA INTERACTIONS

该项目的主要目标是描述 DNA上的多价阳离子结合环境，并探索如何 这些环境在生物学上的变化过程中 重要的DNA结构转换，B-Z转换。 具体地，在以下文献中提出了一系列59 Co NMR测量： 顺序（1），以澄清59钴核磁共振弛豫行为的钴 （NH3）63+结合到DNA，特别是关于影响 阳离子在DNA表面的迁移率（2），以检查碱基 组成、序列和DNA长度对Co（NH3）63+结合的影响 强度和异质性;（3）监测 Co（NH3）63+对合成DNA的B-Z跃迁的影响。额外 实验提出使用13 C和15 N NMR测量， 顺序（1）表征稀溶液行为 特异性标记的多胺（2），以确定局部pKa 与DNA结合的多胺（3），以表征多胺结合 天然的、合成的和寡聚DNA（4），以检查 多胺的迁移率被困在DNA表面附近和（5）， 探针多胺参与B-Z转换。

The primary objectives of this project are to characterize multivalent cation binding environments on DNA and to explore how these environments change over the course of a biologically important DNA structural transition, the B-Z transition. Specifically, a series of 59 Co NMR measurements are proposed in order (l) to clarify the 59 Co NMR relaxation behavior of Co (NH3)63+ bound to DNA, in particular with respect to the influence of cation mobility on the surface of the DNA (2) to examine base composition, sequence and DNA length effects on Co(NH3)63+ binding strength and heterogeneity and (3) to monitor the state of Co(NH3)63+ over the B-Z transition of synthetic DNA. Additional experiments are proposed using 13C and 15N NMR measurements in order (1) to characterize the dilute-solution behavior of specifically labeled polyamines (2) to determine the local pKa's of polyamines bound to DNA (3) to characterize polyamine binding to natural, synthetic and oligomeric DNA's (4) to examine the mobility of polyamines trapped near the DNA surface and (5) to probe polyamine involvement in the B-Z transition.