氧化和减少的二进制蛋白质复合体说明了对比的CID和SID电荷分割
Mengxuan Jia1,2, Yang Song1, Chen Du1,2
1The Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States.
Journal of the American Society for Mass Spectrometry
|August 17, 2023
概括
碰撞诱导解离 (CID) 重组蛋白质复合体,而表面诱导解离 (SID) 将它们对称地分离. 气相蛋白质解离揭示了电荷依赖的展开和重组特性,受碰撞方法的影响.
科学领域:
- 生物物理化学 生物物理化学
- 质谱测量质量谱测量
- 蛋白质化学 蛋白质化学
背景情况:
- 蛋白质复合体的气相解离是复杂的,受蛋白质结构,灵活性和解离技术等因素的影响.
- 了解电荷分离对于解释生物分子组件的质谱数据至关重要.
研究的目的:
- 研究两种含氨酸的同分蛋白质在碰撞诱导解离 (CID) 和表面诱导解离 (SID) 期间的电荷分离行为.
- 阐明二硫化物键的减少和电荷状态对解离路径的影响.
主要方法:
- 在β-乳球蛋白和α-乳蛋白上利用碰撞诱导解离 (CID) 和表面诱导解离 (SID).
- 分析了电荷分离,碰撞截面 (CCS),稳定性和展开/重组性质.
- 对完整的和减少的二硫化物键的解离结果进行了比较,并跨越了不同的电荷状态.
主要成果:
- CID主要是诱导重组,而SID则倾向于对称的电荷分割和单体分离.
- 与较高电荷状态的CID相比,减电CID前体表现出较小的CCS,更大的稳定性和更对称的电荷分布.
- 气体碰撞显示了电荷依赖的重组,而表面碰撞则促进了对称的单体分离.
结论:
- CID涉及债券通过多次低能碰撞的连续重组,有利于重组.
- SID利用大能量跳跃,在分子内断裂的基础上优先地断裂分子间键,从而导致对称解离.
- 这两种方法都产生了重组的前体,但SID对于对称的电荷分割更有效.
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