化Hex-HexNAc分糖的碰撞诱导的解离机制
Hock-Seng Nguan1, Shang-Ting Tsai1, Chia Yen Liew1,2,3
1Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166, Taipei 10617, Taiwan. ckni@po.iams.sinica.edu.tw.
Physical chemistry chemical physics : PCCP
|August 11, 2023
概括
区分碳水化合物异常是具有挑战性的. 碰撞诱导解离 (CID) 质谱学 (MS/MS) 揭示了银河糖-N-乙银河糖胺 (Gal-GalNAc) α和β异常体之间的结构差异,有助于寡糖类分析.
科学领域:
- 分析化学 分析化学
- 葡萄糖生物学 葡萄糖生物学
- 计算化学的计算化学
背景情况:
- 碳水化合物结构的阐明,包括异构的配置,是复杂的.
- 质谱学,特别是CID-MS/MS,对于碳水化合物分析至关重要.
- 了解解离机制是解释MS/MS数据的关键.
研究的目的:
- 为了研究银河糖-N-乙银河糖胺 (Gal-GalNAc) 和葡萄糖-N-乙糖胺 (Glc-GlcNAc) 分糖的碰撞诱导解离 (CID) 机制.
- 使用CID-MS/MS.区分这些脱糖的α-和β-异态.
- 为了将实验CID-MS/MS数据与量子化学计算相关联.
主要方法:
- 对Gal-GalNAc和Glc-GlcNAc分糖进行了碰撞诱导解离 (CID) 双重质谱 (MS/MS).
- 量子化学计算被用来研究解离路径和能量障碍.
- 同位素标记被用来验证计算发现.
主要成果:
- 离子添加物的CID-MS/MS光谱显示了Gal-GalNAc的α-和β-异常体之间的明显差异,但不是Glc-GlcNAc.
- 计算分析显示,与α-anomer相比,Gal-GalNAc的β-anomer在解离障碍中的差异较小.
- 计算结果与来自同位素标记分糖的实验数据保持一致.
结论:
- 基和N-乙基的方向影响CID解离路径.
- 在CID-MS/MS中,可以区分Gal-GalNAc分糖的α-和β-异态.
- 这项研究提供了对特定非糖类的CID机制的洞察,有助于确定寡糖类中的异构配置.
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