School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Analyst. 2020 Oct 21;145(20):6632-6638. doi: 10.1039/d0an00778a. Epub 2020 Aug 14.
The isomeric amino acids l-leucine, l-isoleucine and l-allo-isoleucine, are essential to many vital biological processes and are therefore of interest to the fields of metabolomics and proteomics. Their discrimination can be problematic however due to their isomeric natue. This study demonstrates a systematic investigation of the fragmentations of l-leucine, l-isoleucine and l-allo-isoleucine in combination with a thorough theoretical rationalisation. Collision induced dissociation (CID) tandem mass spectra (MS/MS) of all three amino acids were collected under a range of different collision energies to identify spontaneous and sequential fragmentation processes. We demonstrate that the three structural isomers can be distinguished by their CID MS/MS spectra, and additional computational modelling is used to rationalise these differences.
L-亮氨酸、L-异亮氨酸和 L-别异亮氨酸等立体异构氨基酸对于许多重要的生命过程都是必不可少的，因此它们是代谢组学和蛋白质组学领域的研究重点。然而，由于它们的立体异构性质，对它们进行区分可能会比较困难。本研究结合深入的理论推理，对 L-亮氨酸、L-异亮氨酸和 L-别异亮氨酸的片段化进行了系统的研究。在一系列不同的碰撞能量下收集了这三种氨基酸的碰撞诱导解离（CID）串联质谱（MS/MS），以鉴定自发和顺序的碎裂过程。我们证明，这三种结构异构体可以通过它们的 CID MS/MS 谱来区分，并使用额外的计算建模来合理化这些差异。
