Characterization of cardiolipin from Escherichia coli by electrospray ionization with multiple stage quadrupole ion-trap mass spectrometric analysis of [M-2H+Na]- ions
Characterization of cardiolipin from Escherichia coli by electrospray ionization with multiple stage quadrupole ion-trap mass spectrometric analysis of [M-2H+Na]- ions
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DOI：
10.1016/j.jasms.2005.11.019
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发表时间：
2006-03-01
影响因子：
3.2
通讯作者：
Turk, J
中科院分区：
文献类型：
--
作者：
Hsu, FF;Turk, J
我们用电喷雾电离（EST）的多级离子阱（IT）质谱方法对心磷脂（CL）的[M - 2H + Na]（-）离子进行了结构表征，心磷脂（CL）是一种1,3-双磷脂酰-sn-甘油，分别由四个脂肪酰基链和三个甘油骨架组成，分别称为a、B和中心甘油（见方案1）。在碰撞激活解离（CAD）之后，CL的[M - 2H + Na]（-）离子产生两个突出的片段离子，它们分别是由含有A或B甘油的二酰基甘油部分的不同损失引起的。对两个位于中心甘油的1'-或3'-位置上的磷脂酰基团的初步分配是基于这样一种观察，即由于失去含有甘油B的二酰基甘油部分而产生的离子比含有甘油a的离子更丰富。包括脂肪酰基取代基的身份和脂肪酰基取代基在甘油骨架（甘油A和B）上的位置，由MS3实验确定，MS3实验给出了包含几组突出离子的光谱，为甘油A和甘油B上的脂肪酰基取代基的结构分配提供了信息。这种方法允许从大肠杆菌分离的混合物中分离出CL的结构，包括由各种异构体组成的物种。待详细揭晓。
We report a multiple-stage ion-trap (IT) mass spectrometric approach with electrospray ionization (EST) for structural characterization of the [M - 2H + Na](-) ion of cardiolipin (CL), a 1,3-bisphosphatidyl-sn-glycerol that consists of four fatty acyl chains and three glycerol backbones designated as A, B, and central glycerol, respectively (see Scheme 1). Following collisionally activated dissociation (CAD), the [M - 2H + Na](-) ions of CL yield two prominent fragment ions that arise from the differential losses of the diacylglycerol moieties containing A or B glycerol, respectively. The tentative assignment of the two phosphatidyl moieties attached to the 1'- or 3'-position of the central glycerol is based on the observation that the ions arising from loss of the diacylglycerol moiety containing glycerol B is more abundant than that containing glycerol A. The structures of the above two ions, including the identities of the fatty acyl substituents and the position of fatty acyl substituents on the glycerol backbones (glycerol A and B) are determined by MS3 experiments that give spectra comprising several sets of prominent ions informative for the structural assignment of the fatty acyl substituents on the glycerol A and glycerol B. This method permits the structures of CL in a mixture isolated from Escherichia coli, including species that consist of various isomers, to be unveiled in detail.