Quadrupole ion-trap mass spectrometry to locate fatty acids on lipid A from Gram-negative bacteria
Quadrupole ion-trap mass spectrometry to locate fatty acids on lipid A from Gram-negative bacteria
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DOI：
10.1016/s0003-2697(02)00004-0
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发表时间：
2002-08-01
影响因子：
2.9
通讯作者：
Weintraub, A
中科院分区：
文献类型：
--
作者：
Kussak, A;Weintraub, A
用电喷雾电离(ESI)和离子俘获质谱仪对两株不同酰化程度的福氏志贺氏菌的脂多糖温和酸解释放的类脂A的结构进行了表征。脂类A以负离子模式用电喷雾电泳法分析。通过多阶段裂解(MSN)，可以确定脂肪酸在双糖主链上的酰化程度和位置。通过MSN技术可以确定酰化程度，其中在每个MS阶段，母离子是其中一个脂肪酸已被消除的离子。确定脂肪酸位置的一种方法是从含有不同数量脂肪酸的母体离子中识别还原糖的跨环片段。另一种方法是确定靠近磷酸基团的脂肪酸可能是由电荷驱动释放的。此外，脂肪酸还通过电荷远程碎裂机制被消除。综合数据表明，离子陷阱质谱仪在这类分析中是有用的。(C)2002年埃尔塞维尔科学公司(美国)。版权所有。
The structure of lipid A released by mild acid hydrolysis from lipopolysaccharide from two strains of Shigella flexneri with different degrees of acylation was characterized using electrospray ionization (ESI) and ion-trap mass spectrometry. The lipid A was analyzed underivatized with ESI in negative-ion mode. With multiple stages of fragmentation (MSn), both the degree of acylation and the positions of the fatty acids on the disaccharide backbone could be determined. It was possible to determine the degree of acylation by the MSn technique, where in each MS stage the parent ion was an ion where one fatty acid had been eliminated. One way to determine the location of the fatty acids was by identifying cross-ring fragments of the reducing sugar from parent ions containing different numbers of fatty acids. Another was by identifying a possible charge-driven release of fatty acids situated close to a phosphate group. The fatty acids were otherwise eliminated by a charge-remote fragmentation mechanism. The combined data show the usefulness of ion-trap mass spectrometers for this type of analysis. (C) 2002 Elsevier Science (USA). All rights reserved.