POST SOURCE DECAY PROMPT FRAGMENT IONS FROM PEPTIDES IN MALDI TOF MS

MALDI TOF MS 中肽的源衰变后提示片段离子

• 批准号: 6258776
• 负责人: JOHN ALLISON
• 金额: $ 0.16万
• 依托单位: MICHIGAN STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-06-01 至 1999-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6258776
• 关键词: biological products; biomedical equipment development; biomedical resource; biotechnology; proteins; technology /technique development

In the MALDI analysis of peptides and proteins, these analytes appear as a single species, usually in protonated form, in the linear TOF mass spectra. MS/MS spectra can be collected, since post-source decay appears to occur . However, by using a combination of sample preparation methods and delayed extraction, fragment ions can be generated in the linear TOF MALDI spectrum due to prompt fragmentation (PF) in the ion source. If PF can be optimized, then structural information becomes available from MALDI TOF instruments that only offer the linear TOF option. More importantly, these fragment ions can be selected for the PSD experiment, and spectra of the fragment ions can be obtained. This leads to MSn capabilities that are not currently available in the MALDI TOF instruments that use reflectron technology. Consider the PSD spectrum of an intact protonated peptide molecule. The peptide has many basic sites, so the PSD spectrum contains fragments from many structural forms of the precursor. The fragment ions observed reflect preferred sites of protonation. In contrast, consider PSD on a high mass fragment ion such as a yn ion, which has a specific structure - with the fragment peptide protonated at the N-terminus. MS/MS spectra of this ion will be very different than that of the protonated molecule, yielding products of charge-remote reactions, similar to those we encounter when working with charged derivatives. The ability to generate prompt fragments in the ion source of the MALDI experiment for peptides offers additional options for obtaining sequence information.

在对肽和蛋白质的MALDI分析中，这些分析物 通常以质子化形式出现，以线性形式出现 TOF质谱。 可以收集MS/MS光谱，因为后源 衰减似乎发生了。 但是，通过使用样品组合 制备方法和延迟提取，碎片离子可以是 由于迅速而产生的线性TOF MALDI频谱 离子源中的碎片（PF）。 如果可以优化PF，则 从Maldi TOF仪器获得结构信息 仅提供线性TOF选项。 更重要的是，这些 可以为PSD实验选择片段离子，而光谱 可以获得片段离子。 这导致了MSN功能 当前使用的Maldi TOF仪器中尚未使用 反射量技术。 考虑完整的PSD频谱 质子化肽分子。 肽有许多基本地点，所以 PSD光谱包含来自许多结构形式的片段 前体。 观察到的碎片离子反映了首选位点 质子化。 相反，考虑高质量片段离子上的PSD 例如具有特定结构的Yn离子 - 带有片段 在N末端质子化的肽。 该离子的MS/MS光谱将 与质子化分子的不同，屈服 电荷示射反应的产物，类似于我们遇到的产品 与带电的衍生工具一起工作时。 生成提示的能力 MALDI实验的离子源的片段 提供获得序列信息的其他选项。