Identification of Double Bond Position Isomers in Unsaturated Lipids by m-CPBA Epoxidation and Mass Spectrometry Fragmentation
Identification of Double Bond Position Isomers in Unsaturated Lipids by m-CPBA Epoxidation and Mass Spectrometry Fragmentation
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DOI：
10.1021/acs.analchem.8b04905
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发表时间：
2019-02-05
影响因子：
7.4
通讯作者：
Li, Lingjun
中科院分区：
文献类型：
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作者：
Feng, Yu;Chen, Bingming;Li, Lingjun
脂质是高度多样化的生物分子，与多种生物功能相关，包括结构组成、能量储存和信号转导。这是至关重要的，以表征脂质结构异构体，并进一步了解其生物学作用。不饱和脂质含有一个或多个碳碳双键。确定双键位置是不饱和脂质表征的主要挑战。最近，通过质谱（MS）分析对双键定位已经取得了一些进展。然而，其中许多研究需要复杂的化学反应或具有特殊裂解技术的先进质谱仪，这限制了在脂质组学研究中的应用。在这里，创新的间氯过苯甲酸（m-CPBA）环氧化反应与碰撞诱导解离（CID）-MS/MS策略偶联，为不饱和脂质组学分析提供了新的工具。m-CPBA具有高专一性，可实现快速环氧化反应。在几分钟内实现完全衍生化，而没有过度氧化的副产物。此外，16 Da质量差的诊断离子对表明在MS/MS谱中的碳-碳双键的定位。用这种策略评估了多种脂质类别，并产生了丰富的片段用于结构分析。使用这种策略的酵母提取物的不饱和脂质分析需要不到30分钟，证明了通过这种方法进行高通量脂质组学分析的潜力。本研究为高通量、低仪器要求的不饱和脂质分析提供了一种新的方法，可广泛应用于脂质组学分析。
Lipids are highly diverse biomolecules associated with several biological functions including structural constituent, energy storage, and signal transduction. It is essential to characterize lipid structural isomers and further understand their biological roles. Unsaturated lipids contain one or multiple carbon carbon double bonds. Identifying double bond position presents a major challenge in unsaturated lipid characterization. Recently, several advancements have been made for double bond localization by mass spectrometry (MS) analysis. However, many of these studies require complex chemical reactions or advanced mass spectrometers with special fragmentation techniques, which limits the application in lipidomics study. Here, an innovative meta-chloroperoxybenzoic acid (m-CPBA) epoxidation reaction coupling with collision-induced dissociation (CID)-MS/MS strategy provides a new tool for unsaturated lipidomics analysis. The rapid epoxidation reaction was carried out by m-CPBA with high specificity. Complete derivatization was achieved in minutes without overoxidized byproduct. Moreover, diagnostic ion pair with 16 Da mass difference indicated localization of carbon-carbon double bond in MS/MS spectra. Multiple lipid classes were evaluated with this strategy and generated abundant fragments for structural analysis. Unsaturated lipid analysis of yeast extract using this strategy took less than 30 min, demonstrating the potential for high-throughput lipidomics analysis by this approach. This study opens a door for high throughput unsaturated lipid analysis with minimal requirement for instrumentation, which could be widely applied in lipidomics analysis.