Structural analysis of underivatized neutral human milk oligosaccharides in the negative ion mode by nano-electrospray MSn (Part 2:: Application to isomeric mixtures)
Structural analysis of underivatized neutral human milk oligosaccharides in the negative ion mode by nano-electrospray MSn (Part 2:: Application to isomeric mixtures)
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DOI：
10.1016/s1044-0305(02)00646-3
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发表时间：
2002-11-01
影响因子：
3.2
通讯作者：
Stahl, B
中科院分区：
文献类型：
--
作者：
Pfenninger, A;Karas, M;Stahl, B
在负离子模式下，利用四极杆离子阱质谱仪（QIT - MS）中的纳升电喷雾电离（ESI）技术对来自混合人乳的异构中性低聚糖的复杂混合物进行了分析。由于中性低聚糖的去质子化分子遵循独特的裂解规则，这些规则已通过使用模型化合物阐明（见[1]），从连续的碰撞诱导解离（CID）实验中获得的光谱能够区分这种高度复杂混合物中的异构体。利用这种方法，已鉴定出具有先前未知异构结构的新型人乳低聚糖，例如，可以精确确定三种岩藻糖基化乳糖 - N - 六糖异构体的存在，这些异构体以前未曾被描述过：（1）岩藻糖（α1→2）半乳糖（β1→3）N - 乙酰氨基葡萄糖（β1→3）半乳糖（β1→4）N - 乙酰氨基葡萄糖（β1→3）半乳糖（β1→4）葡萄糖，（2）半乳糖（β1→4）N - 乙酰氨基葡萄糖[（α1→3）岩藻糖]（β1→3）半乳糖（β1→4）N - 乙酰氨基葡萄糖（β1→3）半乳糖（β1→4）葡萄糖，（3）半乳糖（β1→4）N - 乙酰氨基葡萄糖（β1→3）半乳糖（β1→4）N - 乙酰氨基葡萄糖[（α1→3）岩藻糖]（β1→3）半乳糖（β1→4）葡萄糖。（C）2002年美国质谱学会。
A complex mixture of isomeric neutral oligosaccharides from pooled human milk was analyzed by nano-electrospray ionization (ESI) in a quadrupole ion trap mass spectrometer (QIT-MS) in the negative ion mode. Since deprotonated molecules of neutral oligosaccharides follow distinct fragmentation rules, which have been elucidated by using model compounds (see [1]), spectra obtained from consecutive CID experiments allowed the differentiation of isomers out of this highly complex mixture. With this method new human milk oligosaccharides of previously unknown isomeric structures have been identified, e.g., the occurence of three isomeric fucosylated lacto-N-hexaoses could be determined precisely, which have not been described before: (1) Fuc (alpha1 --> 2) Gal (beta1 --> 3) GlcNac (beta1 --> 3) Gal (beta1 --> 4) GlcNac (beta1 --> 3) Gal (beta1 --> 4) Glc, (2) Gal (beta1 --> 4) GlcNAc [(alpha1 --> 3) Fuc] (beta1 --> 3) Gal (beta1 --> 4) GlcNac (beta1 --> 3) Gal (beta1 --> 4) Glc, (3) Gal (beta1 --> 4) GlcNAc (beta1 --> 3) Gal (beta1 --> 4) GlcNac [(alpha1 --> 3) Fuc] (beta1 --> 3) Gal (beta1 --> 4) Glc. (C) 2002 American Society for Mass Spectrometry.