Towards enhanced control of the dissociation chemistry of peptides

Nicolas C.教授佛罗里达大学的Polfer得到化学系化学测量和成像（CMI）项目的支持，研究通过质谱分析蛋白质时发生的化学反应。 该项目将扩大范围，提高从母体蛋白质产生的肽离子碎片模式的质谱表征的保真度。 这又提高了复杂生物样品中蛋白质的高通量鉴定的可靠性。 生命科学的进步依赖于可靠的蛋白质鉴定结果与互补的基因组学和代谢组学信息的整合。 在这方面，该项目将为蛋白质的鉴定提供新的途径，从而促进我们对生命过程的理解。 此外，本研究开发的光谱技术也可能应用于其他化学领域，如机械有机化学。本研究团队正在开发的分析质谱和光谱方法主要用于探测通过碰撞诱导解离（CID）将肽片段化时发生的化学反应，以便通过质谱法进行肽和蛋白质测序。 分析激光光谱技术，特别是红外多光子解离（IRMPD）和低温冷却三维离子阱中的双激光泵浦探测方案，将用于：1）提供对发生的不稳定和自由基重排化学的更深入的理解，2）研究这些重排反应的动力学，以及3）开发能够在解离化学中进行更多控制的方法，用于改进肽和蛋白质的结构测定。 该研究对蛋白质的从头测序和肽序列上翻译后修饰的定位具有重要意义。 在这项研究的过程中，研究生正在接受最先进的质谱和光谱技术的培训。 拟议研究的技术和结果将通过针对高中科学教师的研讨会传达给高中学生。

Professor Nicolas C. Polfer of the University of Florida is supported by the Chemical Measurement and Imaging (CMI) Program in the Division of Chemistry to study the chemistry that takes place when proteins are analyzed by mass spectrometry. The project will expand the scope and improve the fidelity of mass spectrometric characterization of the fragmentation patterns of peptide ions generated from parent proteins. This, in turn, improves the reliability of the high throughput identifications of proteins in complex biological samples. Advances in life sciences depend on the integration of reliable protein identification results with complimentary genomic and metabolomic information. In this context, the project will provide new avenues for the identification of proteins and hence advance our understanding of life processes. In addition, the spectroscopic techniques developed in this work may also lead to applications in other areas of chemistry, such as mechanistic organic chemistry.The analytical mass spectrometric and spectroscopic methods the research team is developing are focused on probing the chemistry that takes place when peptides are fragmented by collision-induced dissociation (CID) for the purpose of peptide and protein sequencing by mass spectrometry. Analytical laser spectroscopy techniques, in particular infrared multiphoton dissociation (IRMPD) and two-laser pump-probe schemes in a cryogenically-cooled 3-D ion trap, will be employed to: 1) provide a deeper understanding of labile and radical rearrangement chemistries that take place, 2) study the dynamics of these rearrangement reactions, and 3) develop methodologies that enable more control in the dissociation chemistry, for improved structural determination of peptides and proteins. The proposed research is of significance to de novo protein sequencing and for the location of posttranslational modifications on the peptide sequence. In the course of this research, graduate students are being trained in state-of-the-art mass spectrometric and spectroscopic techniques. The technologies and the results of the proposed research will be communicated to high school students through workshops aimed at high school science teachers.