圣诞节:基拉尔对同标签策略,用于对等分子氨基酸的复杂绝对量化
Zhijun Zhu1, Shuling Xu2, Zicong Wang2
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
Analytical chemistry
|November 30, 2023
概括
新的合标记试剂可以精确测量生物样本中的d-氨基酸 (d-AAs) 和l-氨基酸 (l-AAs). 这种圣诞战略改善了低丰度d-AAs的检测,为神经疾病提供了洞察力.
科学领域:
- 生物化学 生物化学
- 分析化学 分析化学
- 神经科学是一个神经科学.
背景情况:
- D-氨基酸 (d-AAs) 在神经过程中起着至关重要的作用,但由于难以将它们与l-氨基酸 (l-AAs) 分开,因此对它们的分析具有挑战性.
- 目前用于d-AA检测的质谱方法的灵敏度较低,缺乏适合的内部标准来准确量化.
- 准确量化d-AAs和l-AAs对于了解它们在健康和疾病中的作用至关重要.
研究的目的:
- 开发用于分离和定量d-和l-氨基酸的新性衍生试剂.
- 在复杂的生物矩阵中建立一个多重化策略来绝对量化氨基酸反体.
- 通过量化它们在小鼠大脑样本中的水平来研究d-AAs在衰老和阿尔茨海默病 (AD) 中的作用.
主要方法:
- 已验证的N,N-二甲基-l-氨酸 (l-DiLeu) 和N,N-二甲基-d-氨酸 (d-DiLeu) 作为20对d/l-AAs的奇拉衍生试剂.
- 开发了一种4个复合的同位素标记策略 (CHRISTMAS:为多重绝对量化而采用合对同位素标记策略) 用于单步,方位分子解析的量化.
- 利用离子流动性碰撞横截面 (CCS) 调整来过干扰并提高定量准确性.
主要成果:
- 在野生类型和阿尔茨海默病小鼠大脑中成功量化了20个l-AAs和5个d-AAs.
- 克里斯斯策略显著提高了信号强度,改善了低丰度AA的检测和量化,特别是d-AA.
- 使用配对的d-和l-DiLeu试剂,以提高精度证明了d-AA和l-AA的绝对量化可行性.
结论:
- 克里斯马斯策略为复杂的生物样本中氨基酸的反原体解析量化提供了一种强大而敏感的方法.
- 该方法能够准确地对d-AAs和l-AAs进行绝对量化,克服了以前的分析限制.
- 在老化和AD小鼠大脑中确定了某些d-AAs的显著存在和差异性趋势,为神经退行提供了新的见解.
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