Postdoctoral Fellowship: MPS-Ascend: Elucidation of Peptide Scrambling in Collision Induced Dissociation: Energetic and Mechanistic Analysis via Guided Ion Beam Mass Spectrometry

Evan H. Perez被授予NSF数学和物理科学提升博士后研究奖学金（NSF MPS-Ascend），以开展一项与扩大STEM中代表性不足群体参与相关的研究和活动计划。Perez博士的研究项目名为“MPS-Ascend：在碰撞诱导解离中肽混乱的解析：通过引导离子束质谱的能量和机制分析”，由一位赞助科学家指导。该奖学金的主办机构是犹他大学，赞助科学家是彼得·b·阿门特劳特博士。本研究旨在通过使用离子束质谱法来观察能量分辨碰撞事件，并利用电子结构计算对这些能量进行建模，从而加深对肽碎片和重排机制的理解。该提案将使用聚甘氨酸聚合物离子进行竞争阈值分析和电子结构计算，以阐明观察到的破碎事件的关键化学途径。拟议的研究将调查从四甘氨酸到六甘氨酸的肽长度在大环结构形成中的作用，大环结构是在分子内断裂事件称为“混乱”之前形成的。这项工作将实现行波离子迁移率SLIM（无损离子操作结构）实验，以允许特定构象的碎片分析以及碎片离子的构象分析。所提出的研究将使破碎方法（硬单碰撞与软碰撞加热）的比较和构象与机制的关联成为可能。这项工作的成功实施可能会提高人们对质谱测序的理解，这将对蛋白质序列的确定和蛋白质组学领域的发展产生重大影响。PI计划指导来自代表性不足的少数群体的本科生和研究生进行研究项目，包括质谱技术培训和学习量子化学计算。PI打算与犹他大学的STEM行动中心一起参与潜在的招聘活动，并指导来自代表性不足群体的学生。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Evan H. Perez is awarded an NSF Mathematical and Physical Sciences Ascending Postdoctoral Research Fellowship (NSF MPS-Ascend) to conduct a program of research and activities related to broaden participation by groups underrepresented in STEM. This fellowship to Dr. Perez supports the research project entitled “MPS-Ascend: Elucidation of Peptide Scrambling in Collision Induced Dissociation: Energetic and Mechanistic Analysis via Guided Ion Beam Mass Spectrometry” under the mentorship of a sponsoring scientist. The host institution for the fellowship is the University of Utah, and the sponsoring scientist is Dr. Peter B. Armentrout.This proposal seeks to deepen the understanding of peptide fragmentation and rearrangement mechanisms by using Guided Ion Beam Mass Spectrometry to observe energy-resolved collision events and model these energies using electronic structure calculations. The proposal will use polyglycine polymer ions to perform competitive threshold analysis and electronic structure calculations to elucidate the key chemical pathways for the observed fragmentation events. The proposed research will investigate the role of the peptide length from tetraglycine up to hexaglycine in the formation of macrocyclic structures which precedes the intramolecular fragmentation events known as “scrambling.” The work will implement traveling wave ion mobility SLIM (Structures for Lossless Ion Manipulation) experiments to allow for conformation specific fragmentation analysis as well as conformer analysis of the fragment ions. The proposed studies will enable comparison of fragmentation methods (hard single collision versus soft collisional heating) and correlation of conformation with mechanism. Successful implementation of this work may lead to improved understanding of peptide sequencing by mass spectrometry which could have significant impacts on determining protein sequences and advancing the proteomics field.The PI plans to mentor undergraduate and graduate students from underrepresented minority groups in research projects involving training in mass spectrometric techniques and learning quantum chemical calculations. The PI intends to participate with the STEM Action Center of the University of Utah in potential recruiting activities and mentoring of students from underrepresented groups.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.