CHAR OF CARDIOLIPIN FROM ESCHERICHIA COLI BY ELECTROSPRAY IONIZATION WITH

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 我们报道了用电喷雾电离(ESI)的多级离子陷阱(IT)质谱学方法表征心磷脂(CL)的[M-2H+Na]-离子的结构。心磷脂是一种1，3-二磷脂酰甘油，由四个脂肪酰链和三个甘油骨架组成，分别命名为A、B和中心甘油。在CAD后，CL的[M-2H+Na]-离子的MS2谱包含两个突出的碎片离子，这两个离子是由涉及A或B甘油的二酰基甘油部分的不同损失造成的。中心甘油的1‘-或3’-位上的两个磷脂酰基部分的初步归属是基于这样的观察，即含有甘油B(或A)的二酰基甘油部分的失去所产生的离子比含甘油A(或B)的离子更丰富。这两个离子的结构，包括脂肪酰基取代基的身份和脂肪酰基取代基在甘油主链(甘油A和甘油B)上的位置，是通过它们的MS3光谱确定的，这些光谱包括几组为它们的测定提供信息的显著离子。这种方法允许从大肠杆菌中分离的混合物中的CL的结构被详细揭示，包括由各种异构体组成的物种。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We report multiple-stage ion-trap (IT) mass spectrometric methods with electrospray ionization (ESI) 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, namely, as A, B and central glycerol, respectively. Following CAD, the MS2-spectrum of the [M - 2H + Na]- ions of CL contains two prominent fragment ions resulting from the differential losses of the respective diacylglycerol moieties involving A or B glycerol. 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 involving glycerol B (or A) is more abundant than that involving glycerol A (or B). The structures of the 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 their MS3-spectra that comprise several sets of prominent ions informative for their determination. 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 details.