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Updated: Feb 27, 2026

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Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
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探索超快速结的潜力,以固定电荷修改的囊素残留物进行封闭
Toma Chowdhury1, Thomas A Shoff1, Colomba Sanchez-Marsetti1
1Department of Chemistry, University of California, Riverside, California 92521, United States.
Journal of the American Society for Mass Spectrometry
|February 26, 2026
概括
使用CAP4的氨酸化为蛋白质组学提供了快速的修改. 这种方法提供了与传统方法相比的蛋白质序列覆盖和鉴定,尽管在质谱学中影响了碎片化模式.
科学领域:
- 蛋白质组学和质谱学
- 化学生物学 化学生物学
- 蛋白质化学 蛋白质化学
背景情况:
- 氨酸 (Cys) 修饰在蛋白质组学中对于生成和质谱 (MS) 识别至关重要.
- 电友性Cys arylation比其他阻断策略少见.
- 一种新型试剂,CAP4,可以实现快速和选择性的电友性Cys arylation.
研究的目的:
- 在不同MS条件下 (HCD和ETD) 用CAP4修改的Cys残留物的碎片化行为.
- 评估CAP4在一个自下而上的蛋白质组学工作流程中的实用性.
- 将CAP4修改效率和结果与标准方法 (乙胺) 进行比较.
主要方法:
- 使用N-methyl-2-methylsulfonylpyridinium (CAP4) 对氨酸残留物进行电友性化.
- 在质谱学中使用高能碰撞解离 (HCD) 和电子转移解离 (ETD) 分析CAP4修饰的.
- 使用模型蛋白质混合物与CAP4和乙胺修饰的bottom-up蛋白质组工作流.
主要成果:
- CAP4修改引入了固定收费,影响HCD和ETD的碎片化路径.
- 在HCD中观察到大量的侧链损失,并在ETD中形成电荷状态依赖的β基.
- 使用CAP4 (5分钟) 与酸 (1小时) 实现了可比的序列覆盖和修改的鉴定.
结论:
- CAP4的修改显著影响了片段的分裂,为解离机制提供了独特的见解.
- 尽管有碎片化影响,但CAP4在自下而上的蛋白质组学中对快速Cys修饰有效.
- 在基于MS的蛋白质组学中,CAP4提供了一种可行的,快速的替代物,用于改善含有Cys的的识别.
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