Fragmentation of negative ions from carbohydrates:: Part 2.: Fragmentation of high-mannose N-linked glycans
Fragmentation of negative ions from carbohydrates:: Part 2.: Fragmentation of high-mannose N-linked glycans
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DOI：
10.1016/j.jasms.2005.01.005
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发表时间：
2005-05-01
影响因子：
3.2
通讯作者：
Harvey, DJ
中科院分区：
文献类型：
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作者：
Harvey, DJ
以中性高甘露糖([Man](5-9)[GlcNAc](2), [Glc](1-3)[Man](4-9)[GlcNAc](2)) n -链聚糖及其2-氨基苯甲酰胺衍生物为原料，在含硝酸铵的甲醇水中喷雾生成[M + NO3]（-）和[M + (NO3)(2)]（2-）离子。两种离子的低能碰撞诱导分解（CID）光谱几乎相同，且以交叉环和c型碎片为主，而正离子的低能碰撞诱导分解（CID）光谱主要含有B型和y型糖苷碎片。这种行为可以通过最初形成的阴离子加合物从各种羟基中提取质子来解释。这些负离子光谱比相应的正离子光谱信息更丰富，并且含有突出的离子，这些离子可以诊断结构特征，例如单个天线的组成，这些特征不易通过其他方法获得。c -离子定义了组成单糖残基的序列。详细的碎片机制提出，以说明许多诊断离子。(c) 2005年美国质谱学会。
[M + NO3](-) And [M + (NO3)(2)](2-) ions were produced by electrospray from neutral high-mannose ([Man](5-9)[GlcNAc](2), [Glc](1-3)[Man](4-9)[GlcNAc](2)) N-linked glycans and their 2-aminobenzamide derivatives sprayed from methanol:water containing ammonium nitrate. Low energy collision-induced decomposition (CID) spectra of both types of ions were almost identical and dominated by cross-ring and C-type fragments, unlike the corresponding spectra of the positive ions that contained mainly B- and Y-type glycosidic fragments. This behavior could be rationalized by an initial proton abstraction from various hydroxy groups by the initially-formed anionic adduct. These negative ion spectra were more informative than the corresponding positive ion spectra and contained prominent ions that were diagnostic of structural features such as the composition of individual antennas that were not easily obtainable by other means. C-ions defined the sequence of the constituent monosaccharide residues. Detailed fragmentation mechanisms are proposed to account for many of the diagnostic ions. (c) 2005 American Society for Mass Spectrometry.