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Updated: Jun 27, 2026

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Synthesis and Mass Spectrometry Analysis of Oligo-peptoids
Published on: February 21, 2018
质子化的序列乱碎片化途径的质子化
Christian Bleiholder1, Sandra Osburn, Todd D Williams
1Department of Molecular Biophysics, Im Neuenheimer Feld 580, German Cancer Research Center, 69120 Heidelberg, Germany.
Journal of the American Chemical Society
|December 6, 2008
概括
片的碰撞诱导解离 (CID) 揭示了b离子快速循环,导致由循环同位素决定的碎片化模式. 这种循环-重新开放机制可以在分析过程中导致序列信息丢失.
科学领域:
- 分析化学 分析化学
- 计算化学计算化学
- 生物化学 生物化学
背景情况:
- 在质谱学中理解片段化对于序列确定至关重要.
- 碰撞诱导解离 (CID) 是一种用于碎的常见技术.
- 在CID过程中N终端b和a离子的行为可能是复杂的,涉及重新安排.
研究的目的:
- 研究特定的N端b和a片段的气相结构和碎片化途径.
- 阐明在b和a离子的CID过程中混杂和重新排列反应的机制.
- 确定循环化对CID碎片化模式的影响.
主要方法:
- 使用碰撞诱导解离 (CID) 的实验调查.
- 使用分子力学和密度函数理论 (DFT) 计算的理论分析.
- 对线性和循环性异构体的碎片化模式的比较.
主要成果:
- 来自各种的b(5) 碎片的低能CID产生了类似的解离模式.
- 质子循环-YAGFL的CID产生了与线性b) 5) 离子相同的碎片和离子丰度,表明了快速循环.
- 计算结果支持循环化重新开放机制,以质子化循环-YAGFL) 在能量上优于线性异构体.
结论:
- 线性b(5) 离子的碎片化光谱由它们的循环同体主导,这是由于快速的循环化和易于相互转换.
- 这种循环再开机制可以导致在CID过程中完全丢失序列信息.
- 对于a(5) 离子的CID,涉及b型杂乱和a --> a*型重排,循环化之后重新开放到线性结构.
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