埃克斯D与EThcD:什么对内生两二硫化的直接测序更好?
Dmitrii M Mazur1,2, Tatiana Yu Samgina1,2, Yury V Vasil'ev3
1Department of Materials Science, MSU-BIT University, Shenzhen 517182, China.
Journal of the American Society for Mass Spectrometry
|November 26, 2025
概括
使用补充性质谱法方法实现了完整的两动物皮肤的直接测序. 电子转移/高能碰撞解离 (EThcD) 和电子exD (ExciD) 碎片化技术为复杂的二硫化物桥接提供了完整的序列覆盖.
科学领域:
- 蛋白质组学是指蛋白质组学.
- 质谱测量质量谱测量
- 生物化学 生物化学
背景情况:
- 两动物皮肤是有价值的,但由于它们的长度,二硫化物桥梁和异构残留,直接测序具有挑战性.
- 传统的测序方法往往需要衍生,这可以通过先进的质谱技术来规避.
研究的目的:
- 评估和比较电子转移/高能碰撞解离 (EThcD) 和电子ExD (ExD/ExciD) 碎片化方法的有效性,以直接测序完整的两动物皮肤.
- 来自Pelophylax ridibundus*的复杂二硫化物桥接的完整序列覆盖.
主要方法:
- 从皮肤分泌物*Pelophylax ridibundus*中直接测序16个完整的.
- 使用电子转移/高能碰撞解离 (EThcD),电子-ExD (ExD) 和电子激发解离 (ExciD) 协奏质谱.
- 分析碎片离子,包括w-离子和d-离子,以区分异构体残留物和确认序列.
主要成果:
- 无论是EThcD还是ExD/ExciD方法都适合用于直接序列.
- ExciD表现出卓越的性能,产生更高的碎片离子丰度,并使所有的完整测序成为可能,包括46-mer.
- 通过对ExciD和EThcD的互补应用,所有16种二硫化物桥接的序列覆盖率达到了100%.
- d-离子对于二硫化环内的测序特别有用,并且在ExD/ExciD模式中更频繁地出现.
结论:
- 结合使用ExciD和EThcD质谱法,为复杂的,完整的两动物皮肤的直接测序提供了强大的和可靠的方法.
- 这种方法克服了长度,二硫化键和异构体残留所带来的挑战,使得完整的序列确定成为可能.
- 这些发现促进了直接测序能力,以挑战蛋白质组学和相关领域的样.
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