Assessing the Biomolecular Structures that Result from Electrospray Ionization

评估电喷雾电离产生的生物分子结构

• 批准号: 10712440
• 负责人: Elyssia S Gallagher
• 金额: $ 33.64万
• 依托单位: BAYLOR UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2028-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10712440
• 关键词: Address; Affect; Binding; Biological; Biological Process; Carbohydrates; Cells; Cellular biology; Charge; Complex; Development; Disease; Disease Progression; Electrospray Ionization; Exhibits; Future; Gases; Glycoconjugates; Goals; Infection; Ions; Isomerism; Ligand Binding; Mass Spectrum Analysis; Metals; Methodology; Methods; Modeling; Molecular; Phase; Polymers; Polysaccharides; Process; Property; Proteins; Research; Research Personnel; Signal Transduction; Sodium; Spectrometry, Mass, Electrospray Ionization; Structure; Techniques; Validation; Work; adduct; analytical method; deprotonation; host-microbe interactions; improved; insight; ion mobility; ionization; ionization technique; molecular dynamics; molecular recognition; novel; pathogen; protein complex; protein structure; protonation; tandem mass spectrometry; tool

Project Summary / Abstract Glycans, heterogeneous polymers of carbohydrates, interact with proteins to initiate a multitude of biologi- cal processes, including molecular recognition, cellular signaling, and host-microbe interactions. Mass spec- trometry (MS) methods have become powerful tools for characterizing the structures of glycans and their inter- actions with proteins. Electrospray ionization (ESI) is a common ionization method for transferring these bio- molecules from solution to the gas-phase for MS analysis. However, both glycans and proteins exhibit struc- tural changes during ESI. Thus, there is a critical need to understand how biomolecular structures are modified during and after the ESI process to determine (1) how researchers can deduce solvated structures from these techniques and (2) how analytical methods can be improved. To address this challenge, the Gallagher lab uses a combination of molecular dynamics (MD) simulations and MS methods to develop a fundamental, molecular perspective of ESI. The Gallagher lab performs MD simulations of ESI to observe carbohydrate ionization using metal ions as charge carriers. However, to more accurately model protein ionization, the Gallagher lab is developing methods to simulate protonation during ESI. These methods will be further developed to examine analyte ionization by deprotonation in negative-ion mode, and then applied to achieve a molecular perspective on the ionization of glycans and proteins. In paral- lel to the MD simulations, the Gallagher lab will perform MS analysis of metal-adducted glycans. Glycans readily ionize by coordinating to metal ions, with different metal-adducts enabling isomeric differentiation in both tandem MS and ion mobility-MS. However, glycans are often analyzed as sodium adducts because so- dium is a ubiquitous contaminant. The Gallagher lab is performing systematic studies examining the relation- ship between metal-ion properties and glycan characterization by MS. Finally, the Gallagher lab is applying native MS to characterize protein complexes. In native MS, noncovalent interactions are maintained in the gas phase; yet past work has suggested that proteins analyzed as positive versus negative ions have differ- ences in gas-phase stability. The Gallagher lab will examine how charging in ESI to form either positive or neg- ative ions is related to gas-phase protein structure, stability, and ligand-binding interactions. The overarching goal of the Gallagher lab is to develop and apply novel methodologies to characterize gly- cans, proteins, and their binding interactions. The research described in this proposal is significant because it will provide a fundamental perspective on ESI-MS and the molecular insights from this research will enable the rational development of future ESI-MS methods for characterizing these molecules. Ultimately, this work will facilitate the analysis of glycans, glycoconjugates, and protein complexes in cell biology and disease states, enabling these methods to be applied to address important biological hypotheses.

项目总结/摘要 聚糖是碳水化合物的异质聚合物，与蛋白质相互作用，引发多种生物学反应。 cal过程，包括分子识别，细胞信号传导和宿主-微生物相互作用。质谱- 质谱（MS）方法已成为表征聚糖结构及其相互作用的有力工具。 与蛋白质的作用。电喷雾离子化（ESI）是用于转移这些生物活性物质的常用离子化方法。 分子从溶液到气相进行MS分析。然而，聚糖和蛋白质都表现出结构， ESI期间的自然变化。因此，迫切需要了解生物分子结构是如何被修饰的 在ESI过程中和之后，以确定（1）研究人员如何从这些化合物中推导出溶剂化结构 （2）分析方法如何改进。 为了应对这一挑战，Gallagher实验室使用了分子动力学（MD）模拟 和MS方法，以发展ESI的基本分子视角。加拉格尔实验室在医学博士 模拟ESI观察使用金属离子作为电荷载体的碳水化合物电离。然而，更多 准确地模拟蛋白质电离，加拉格尔实验室正在开发方法来模拟质子化过程中， ESI。这些方法将进一步发展，以检查分析物电离的去质子在负离子 模式，然后应用于实现对聚糖和蛋白质的电离的分子视角。平行- 除了MD模拟之外，Gallagher实验室还将对金属加合聚糖进行MS分析。聚糖 容易通过与金属离子配位而被取代，不同的金属加合物使得异构体在 然而，聚糖通常作为钠加合物进行分析，因为 铟是普遍存在的污染物。加拉格尔实验室正在进行系统的研究，检查关系- 最后，Gallagher实验室正在申请 天然MS来表征蛋白质复合物。在天然MS中，非共价相互作用维持在 气相;但过去的工作表明，作为正离子和负离子分析的蛋白质有不同的- 气相稳定性。加拉格尔实验室将研究如何在ESI中充电，以形成阳性或阴性， 阳离子与气相蛋白质结构、稳定性和配体结合相互作用有关。 加拉格尔实验室的首要目标是开发和应用新的方法来表征gly- 罐，蛋白质，以及它们的结合相互作用。该提案中描述的研究意义重大，因为它 将提供ESI-MS的基本观点，这项研究的分子见解将使 合理开发用于表征这些分子的未来ESI-MS方法。最终，这项工作将 有助于分析细胞生物学和疾病状态中的聚糖、糖缀合物和蛋白质复合物， 使这些方法能够应用于解决重要的生物学假设。