Dynamics of Excited Electronic States in DNA Strands

化学系化学结构动力学与机制a （CSDM-A）项目资助蒙大拿州立大学的Bern Kohler教授研究双链DNA的光物理学。双链DNA似乎增强了抗光降解的稳定性，科勒小组正在进行详细的调查，以更好地了解这种光化学稳定性的机制基础。在进一步的实验中，科勒教授和他的研究学生将研究DNA在所谓的深共晶溶剂（DES）中的光化学变化。科勒教授的研究在生物学和医学上具有重要意义，因为了解DNA与光相互作用的方式直接关系到了解来自太阳的紫外线损伤皮肤的方式。在科勒实验室工作的学生接受物理化学和生物学方面的培训，为学术或生物技术部门的职业生涯做准备。科勒研究小组包括本科生积极参与真实研究。此外，科勒教授和他的小组成员通过各种既定的项目，如蒙大拿州立大学科学数学资源中心和蒙大拿州空间资助联盟，致力于蒙大拿州K-12学生和教师的外展。Bern Kohler教授和他的研究小组将使用超快激光方法进行详细的光化学实验，以研究双链DNA有趣的光物理学。关于双链DNA在电子激发后究竟如何发生光化学衰变的问题仍然存在。在本次奖项中，科勒教授和他的团队将进行一系列实验，以更好地了解光化学的细节。实验内容包括：(1)利用时间分辨红外光谱（TRIR）研究AT和GC DNA的协同质子电子转移（CPET）；(2)与美国空军学院的Kimberly de La Harpe博士合作进行了一项关于用TRIR光谱研究寡核苷酸光化学的研究，该研究之前已经用紫外/可见瞬态吸收（TA）光谱进行了研究；(3)与美国犹他大学Cynthia Burrows教授合作，对Kohler基团合成的迷你双工化合物进行了TRIR和TA研究；(4)研究DES中DNA的光化学。实验工作将受益于意大利国家研究委员会生物结构和生物成像研究所的Roberto Improta教授的理论小组提供的见解。

With this awwrd, the Chemical Structure Dynamics and Mechanisms-A (CSDM-A) Program of the Division of Chemistry is funding Professor Bern Kohler of Montana State University to investigate the photophysics of double-stranded DNA. Double-stranded DNA appears to have enhanced stability against photo-degradation, and the Kohler group is undertaking a detailed investigation to better understand the mechanistic underpinnings of this photochemical stability. In additional experiments, Prof. Kohler and his research students will investigate how the photochemistry of DNA differs in so-called deep eutectic solvents (DES). Prof. Kohler's research has important implications in biology and medicine, in that understanding the way DNA interacts with light has direct bearing on understanding the ways that ultraviolet light from the sun can damage skin. Students working in the Kohler laboratory receive training at the interface of physical chemistry and biology, as preparation for careers in the acedemic or biotechnology sectors.The Kohler research group includes active participation of undergraduate students in authentic research. In addition, Prof. Kohler and his group members are engaged in outreach to K-12 students and teachers in the state of Montana, through a variety of established programs, such as Montana State University's Science Math Resource Center and the Montana Space Grant Consortium.Professor Bern Kohler and his research group will conduct detailed photochemistry experiments using ultrafast laser methods to investigate the interesting photophysics of double-stranded DNA. Questions remain as to how exactly double-stranded DNA photochemically decays after electronic excitation. In the present award, Professor Kohler and his group will conduct a number of experiments to develop a better understanding of the photochemical details. Experiments to be conducted include: (1) a study of concerted proton-electron transfer (CPET) in AT and GC DNA using time-resolved infrared (TRIR) spectroscopy; (2) a collaborative study with Dr. Kimberly de La Harpe of the USAF Academy on the photochemistry of an oligonucleotide with TRIR spectroscopy that has been studied previously with UV/Visible transient absorbance (TA) spectroscopy; (3) a TRIR and TA study of miniduplexes synthesized for the Kohler group in a collaboration with Prof. Cynthia Burrows of the University of Utah; and (4) a new thrust investigating the photochemistry of DNA in DES's. Experimental work will benefit from insight provided by the theoretical group of Professor Roberto Improta of the National Research Council of Italy's Institute of Biostructures and Bioimaging.