STRUCTURE OF DNA--SPECTROSCOPIC STUDIES

DNA的三维结构受碱基序列的影响， 金属离子、化学致癌物和其他物质将通过 真空-紫外圆二色谱(VUV-CD)及其时间分辨 荧光。 DNA碱基的电子态和跃迁，理解 这对CD光谱的解释至关重要，将使用 真空-紫外磁性圆二色谱(VUV-MCD)与荧光 偏振光谱。 一个主要目标是了解为什么VUV-CD是一个更好的指标 螺旋结构的，并且对氢键更敏感 DNA链比常规的、波长更长的CD。 VUV-CD、VUV-MCD、荧光偏振和时间分辨 荧光实验将在国家同步加速器进行 光源。

The three dimensional structure of DNA as influenced by base sequence, metal ions, chemical carcinogens and other agents will be studied by vacuum-ultraviolet circular dichroism (VUV-CD) and time resolved fluorescence. The electronic states and transitions of the DNA bases, understanding of which is crucial to the interpretation of CD spectra, will be studied using vacuum-ultraviolet magnetic circular dichroism (VUV-MCD) and fluorescence polarization spectroscopy. A major goal is understanding why VUV-CD is a better indicator of the helical structure of, and more sensitive to the hydrogen bonding between DNA strands than is conventional, longer wavelength CD. The VUV-CD, VUV-MCD, fluorescence polarization and time-resolved fluorescence experiments will be performed at the National Synchrotron Light Source.