Thermochemistry of Noncovalent Interactions and Metal-Ligand Bonds of Biological Relevance

在这个由化学结构、动力学和机理a （CSDM-A）项目资助的项目中，韦恩州立大学的Mary T. Rodgers教授正在使用质谱技术来获取有关弱相互作用的信息，这些弱相互作用将两个或多个分子结合在一起，而不会形成强的“共价键”。共价键是指两个分子之间实际共享电子。“非共价”相互作用通常比共价键弱。它们的作用包括液体的沸点和昆虫粘在墙壁上的能力。罗杰斯教授的研究重点是与生命系统相关的非共价相互作用，例如金属原子与核分子（这些是DNA的组成部分）和肽分子（蛋白质的组成部分）的结合。这项研究的结果可能会促进我们对生物过程的化学基础的理解，并有助于设计传感生物相关分子的新技术。参与该项目的研究生和本科生将在包括化学、生物化学、化学物理和质谱的多学科研究环境中获得宝贵的经验。由此产生的热化学数据正在被汇编，并通过基于网络的热化学数据库、美国国家标准与技术研究院（NIST）化学网络手册和CRC化学与物理手册提供给社区。在这项工作中，实验测量和理论计算协同结合，阐明了有关非共价相互作用和生物相关金属配体键的定量热化学数据和动力学和结构信息。采用离子束串联质谱（GIBMS）实验研究了目标物质的能量分辨碰撞诱导解离（CID）行为。电子结构计算表征了感兴趣的物种的结构和能量学及其CID途径。实验数据的热化学分析得到了非共价相互作用或金属-配体键在CID上断裂的能量和结构信息，以及观察到的活化解离途径的机制和能量屏障。这项工作的预期结果是继续开发定制的GIBMS仪器和相关的数据分析程序，这可能使未来对日益复杂的系统进行研究成为可能。

In this project funded by the Chemical Structure, Dynamics and Mechanisms-A (CSDM-A) Program in the Division of Chemistry, Professor Mary T. Rodgers of Wayne State University is using mass spectrometry techniques to obtain information about the weak interactions that hold two or more molecules together without the formation of a strong "covalent" bond. Covalent bonds involve the actual sharing of electrons between the two molecules. "Non-covalent" interactions are generally weaker than covalent bonds. They play roles such things as the boiling point of liquids and the ability of insects to stick to walls. Professor Rodgers' research focuses on non-covalent interactions relevant to living systems, for example metal atom binding with nucleic molecules (these are constituents of DNA) and the binding of peptide molecules (constituents of proteins). The results of this research may advance our understanding of the chemical basis for biological processes and aid in the design of new technologies for sensing biologically relevant molecules. Graduate and undergraduate students involved in this project are gaining valuable experience in a multidisciplinary research environment encompassing chemistry, biochemistry, chemical physics and mass spectrometry. The resulting thermochemical data are being compiled and made available to the community via a web-based thermochemical database, the National Institutes of Standards and Technology (NIST) Chemistry Webbook and the CRC Handbook of Chemistry and Physics.In this work, experimental measurements and theoretical calculations are synergistically combined to elucidate quantitative thermochemical data and dynamical and structural information regarding noncovalent interactions and metal-ligand bonds of biological relevance. Guided ion beam tandem mass spectrometry (GIBMS) experiments are employed to probe the energy-resolved collision-induced dissociation (CID) behavior of the species of interest. Electronic structure calculations characterize the structures and energetics of the species of interest and their CID pathways. Thermochemical analysis of the experimental data are yielding energetic and structural information on the noncovalent interactions or metal-ligand bonds that are cleaved upon CID and on the mechanisms and energetic barrier(s) for the observed activated dissociation pathways. Continued development of the custom-built GIBMS instrument and associated data analysis procedures is an expected outcome of this work that may enable future studies on increasingly complex systems.