Merged Beam MALDI TOF-TOF Using Ion-Ion Reactions to Determine Structure of

合并束 MALDI TOF-TOF 使用离子-离子反应确定结构

• 批准号: 8009479
• 负责人: MARVIN L VESTAL
• 金额: $ 15.47万
• 依托单位: VIRGIN INSTRUMENTS CORPORATION
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8009479
• 关键词: Affinity; Biological; Cells; Charge; Chemicals; Complex Mixtures; Cross Reactions; Dissociation; Electron Transport; Electrons; Electrospray Ionization; Elements; Funding; Glycoconjugates; Goals; Ions; Knowledge; Lasers; Lead; Lipids; Mass Spectrum Analysis; Measurement; Measures; Molecular; Molecular Structure; Molecular Weight; Monitor; Oligonucleotides; Oligosaccharides; Optics; Peptides; Performance; Phase; Physiologic pulse; Posttranslational Amino Acid Modification; Process; Production; Property; Proteins; Protocols documentation; Protons; Reaction; Reagent; Relative (related person); Research; Sensitivity and Specificity; Source; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Speed; Structure; System; Techniques; Technology; Temperature; Time; Work; design; driving force; insight; instrument; interest; ion source; ionization; prototype; public health relevance

DESCRIPTION (provided by applicant): Merged Beam MALDI TOF-TOF Using Ion-Ion Reactions to Determine Structure of Biological Molecules Summary The ultimate goals of this research are practical techniques for MALDI-TOF MS-MS on biologically significant molecules using electron transfer dissociation (ETD) of positive ions and proton transfer dissociation (PTD) of negative ions to determine molecular structure. This technology will provide the ability to study ion-ion collision processes under single collision conditions with direct measurement of the results in terms of charge transfer and fragmentation. Reaction cross sections for competing processes will be measured for several types of ion-ion collision processes. The emphasis in the fundamental studies is on reactions that lead to excited ions that dissociate following collision to produce structurally informative fragment ions. Singly charged precursors may be analyzed by employing double charge transfer to first produce excited neutrals that fragment efficiently, and then ionize the fragments by a second collision to produce fragment ions with charge opposite that of the precursor. In addition to fundamental knowledge, this research will provide practical techniques for determining molecular structure of singly and doubly charged molecular ions produced by MALDI. The approach should be applicable to a wide variety of molecules including intact proteins, peptides, oligonucleotides, oligosaccharides, glycoconjugates, lipids, and metabolites, and may provide speed, sensitivity, and specificity for identification and structural elucidation of unknowns that surpasses that available with electrospray ionization and ion traps. The instrument features addition of a second pulsed ion source to a recently developed high- performance MALDI-TOF-TOF MS-MS system. Pulsed beams from the two sources are merged within a collision cell with the pulses accurately synchronized in time, and with the relative velocity of the beams accurately determined and very near zero. The proposed apparatus will allow sensitive measurements of reactions between ions of opposite polarity and between ions and excited neutrals at low translational energies not previously accessible. The internal temperature (or excitation) of the reactants may be quite high but the translational temperatures are very low leading to very high cross sections for these processes. Collisions with reduced mass of 100 Da and relative velocity of 1 m/s correspond to translational energy of 5x10-7 eV, and translational temperature of 6x10-3 K. We are not aware of any previous work on ion-ion collision processes under these conditions. PUBLIC HEALTH RELEVANCE (provided by applicant): The "Holy Grail" of mass spectrometry for biological applications is an instrument that provides accurate molecular weight and complete, unambiguous sequence, including unusual amino acids and post- translational modifications, on proteins present at trace levels in complex mixtures. It should also provide similar information on mass and structure of other biologically significant molecules, including metabolites, lipids, oligosaccharides, glycoconjugates, oligonucleotides, and peptides. This may be it.

描述（申请人提供）：使用离子离子反应合并的束MALDI TOF-TOF-TOF-TOF来确定生物分子的结构总结本研究的最终目标是使用电子转移解离的MALDI-TOF MS-MS对生物学上具有重要意义的分子的实用技术（负离子的阳性离子和质子转移解离（PTD）的ETD）确定分子结构。该技术将提供在单个碰撞条件下研究离子离子碰撞过程的能力，并在电荷传递和分裂方面直接测量结果。将在几种类型的离子离子碰撞过程中测量竞争过程的反应横截面。基本研究的重点是导致激发离子碰撞后解离以产生结构上有用的片段离子的反应。可以通过双电荷转移到第一次产生有效的片段的激发中性，然后通过第二次碰撞将片段电离以产生碎片离子，而片段与前体相反的片段离子，从而分析了单一带电的前体。除了基本知识外，这项研究还将提供实用技术，以确定MALDI产生的单一和双电荷分子离子的分子结构。该方法应适用于多种分子，包括完整的蛋白质，肽，寡核苷酸，寡糖，寡糖，糖缀合物，脂质和代谢产物，并可能提供用于透露不明智的识别和结构性阐明的速度，敏感性和特异性，这些识别和结构性阐明了Electrosprays的识别和结构性电离和离子陷阱。 该仪器在最近开发的高性能MALDI-TOF-TOF-TOF-TOF MS-MS系统中添加了第二个脉冲离子源。来自两个源的脉冲梁在碰撞电池内合并，脉冲随时间准确地同步，并与光束的相对速度准确确定并且非常接近零。所提出的设备将允许对相反极性离子以及离子和激发中性之间的反应进行敏感测量，而在以前无法使用的低平移能。反应物的内部温度（或激发）可能很高，但平移温度非常低，导致这些过程的横截面非常高。质量降低100 dA的碰撞，相对速度为1 m/s，对应于5x10-7 eV的平移能，转化温度为6x10-3 k。我们不知道这些先前在这些下面的离子离子碰撞过程的工作状况。 公共卫生相关性（由申请人提供）：生物应用质谱的“圣杯”是一种提供准确的分子量重量和完整，明确的序列的工具在复杂的混合物中。它还应该提供有关其他具有生物学意义的分子的质量和结构的类似信息，包括代谢物，脂质，寡糖，糖缀合物，寡核苷酸和肽。可能就是这样。