Base Pair Opening in the Origin of DNA Replication

描述：（由申请人提供）遗传信息的传递 活细胞通过将DNA复制成两个相同的拷贝而发生。这 这一过程始于染色体上的特定位点，在那里， 螺旋打开，亲本链分开，以便允许进入， 复制机制的作用。这些特定的站点， 开始通过进化获得了独特的能量特征， DNA解旋元件（DUE）这项研究提出， 本申请的目的是映射在DNA中每个碱基对的开放的能量学。 DNA解旋细菌染色体的元件。选择的方法是 核磁共振（NMR）光谱。1/H和15/N NMR将用于 观察三个DNA双链体的每个沃森-克里克碱基对中的亚氨基质子 包含感兴趣的DUE站点。这些质子的交换率 将通过NMR作为温度的函数来测量， 交换催化剂的浓度。汇率将决定 以及在这些DUE位点中每个碱基对的打开的能量学。这些 高分辨率的能量图将有助于理解 DNA中碱基序列与局部稳定性的基本关系 双螺旋

DESCRIPTION: (provided by applicant) Transmission of genetic information in living cells occurs by replication of the DNA into two identical copies. This process is initiated at specific sites on the chromosomes, where the double helix opens and the parental strands separate in order to allow the entry and the action of the replication machinery. These specific sites where replication begins have acquired through evolution unique energetic features that allow them to function as DNA Unwinding Elements (DUE). The research proposed in this application aims at mapping the energetics of opening of each base pair in the DNA Unwinding Elements of a bacterial chromosome. The method of choice is nuclear magnetic resonance (NMR) spectroscopy. 1/H and 15/N NMR will be used to observe the imino protons in each Watson-Crick base pair of three DNA duplexes containing the DUE sites of interest. The rates of exchange of these protons with solvent will be measured by NMR as a function of temperature and concentration of exchange catalyst. The exchange rates will define the kinetics and energetics of opening of each base pair in these DUE sites. These high-resolution energetic maps will contribute to the understanding of the fundamental relationships between base sequence and local stability in DNA double helices.