Transient Intermediates in Proton and Electron Transfer

在这个由化学系化学结构、动态和机制B计划资助的项目中，西雅图华盛顿大学化学系的Frantisek Turecek教授将开发改进的蛋白质质谱学测序的新方法。这项研究的目的是首先深入了解提供多肽氨基酸序列信息的多肽骨架解离，然后拼接完成亲本蛋白质的序列。蛋白质测序是确定导致许多疾病和退化过程的突变、翻译后修饰和损伤的关键步骤。癌症、帕金森、阿尔茨海默病和衰老都包括蛋白质变化，这是扰乱细胞过程及其调节的主要原因之一。这个研究小组也处于有利地位，可以为不同文化背景的学生提供最高水平的教育和培训，包括那些在物理和生命科学领域代表性不足的学生。质谱仪是蛋白质和多肽分析的首选方法。在所谓的自下而上的方法中，蛋白质或其混合物被酶切成多肽的混合物，然后在线分离和分析。质谱分析提供了关于多肽质量、氨基酸序列和组成的有价值的信息。这些信息可以通过与数据库进行匹配来评估，以找到存在已知基因的通用蛋白质。然而，缺乏基因组数据的生物体的蛋白质，或者由于疾病或损伤而修饰的蛋白质，必须通过所谓的从头测序来分析，这意味着仅从质谱学数据中就可以读出完整的序列。在本项目中，研究和开发了改进从头蛋白质测序的新方法。该项目有几个目标：(1)正在开发一种在固相载体上捕获和化学修饰多肽的新方法，以简化多肽混合物，提高序列读出水平。(2)对电子转移后的多肽离子解离进行基础研究，以确定离子的三维结构和能量沉积的影响。(3)引入了一种新的紫外光解离方法，提供了一种不同的激活方式，使气相多肽离子有效地解离。这些研究的结果将被用来改进目前的多肽离子活化和解离的理论模型，并将其用于预测离子行为。

In this project funded by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division, Professor Frantisek Turecek of the Department of Chemistry at University of Washington, Seattle, will develop new methods for improved protein sequencing by mass spectrometry. The goal of this research is first to gain deep understanding of peptide backbone dissociations that provide information on the peptide amino acid sequence which is then spliced to complete the sequence of the parent protein. Protein sequencing is the critical step in determining mutations, post-translational modifications, and damage that cause many diseases and degenerative processes. Cancer, Parkinson and Alzheimer diseases and aging all include protein changes as one of the major causes disrupting cellular processes and their regulation. This research group is also well-positioned to provide the highest level of education and training for students of different cultural backgrounds including those underrepresented in physical and life sciences. Mass spectrometry is the method of choice for protein and peptide analysis. In the so-called bottom-up approach, the protein or a mixture thereof is enzymatically cleaved to a mixture of peptides that are separated on-line and analyzed. Mass spectrometry analysis provides valuable information on the peptide mass and amino acid sequence and composition. The information can be evaluated by matching against a data base to find the generic protein for which there is a known gene. However, proteins from organisms lacking genome data, or modified proteins due to disease or damage must be analyzed by the so-called de novo sequencing, implying complete sequence readout from the mass spectrometry data alone. In this project, new methods are investigated and developed to improve de novo protein sequencing. The project has several goals: (1) A new method of peptide capture and chemical modification on solid phase support is being developed to simplify peptide mixtures and increase the level of sequence readout. (2) Fundamental studies of peptide ion dissociations following electron transfer will be carried out to determine the effects of ion 3D structure and energy deposition. (3) A new UV photodissociation method is introduced to provide a different means of activation, causing efficient dissociation of gas-phase peptide ions. Results from these studies will be used to refine the current theoretical model of peptide ion activation and dissociation and utilize it for prediction of ion behavior.