Department of Chemistry, University of California , Davis, California 95616, United States.
J Proteome Res. 2012 Mar 2;11(3):1958-68. doi: 10.1021/pr2011439. Epub 2012 Feb 22.
Glycosylation is one of the most common post-translational modifications of proteins and has been shown to change with various pathological states including cancer. Global glycan profiling of human serum based on mass spectrometry has already led to several promising markers for diseases. The changes in glycan structure can result in altered monosaccharide composition as well as in the linkages between the monosaccharides. High-throughput glycan structural elucidation is not possible because of the lack of a glycan template to expedite identification. In an effort toward rapid profiling and identification of glycans, we have constructed a library of structures for the serum glycome to aid in the rapid identification of serum glycans. N-Glycans from human serum glycoproteins are used as a standard and compiled into a library with exact structure (composition and linkage), liquid chromatography retention time, and accurate mass. Development of the library relies on highly reproducible nanoLC-MS retention times. Tandem MS and exoglycosidase digestions were used for structural elucidation. The library currently contains over 300 entries with 50 structures completely elucidated and over 60 partially elucidated structures. This database is steadily growing and will be used to rapidly identify glycans in unknown biological samples.
糖基化是蛋白质最常见的翻译后修饰之一，已经证明它会随着包括癌症在内的各种病理状态而改变。基于质谱的人血清聚糖的全局分析已经产生了几种有前途的疾病标志物。糖链结构的变化会导致单糖组成的改变，以及单糖之间的连接发生改变。由于缺乏糖模板来加速鉴定，因此无法进行高通量糖链结构阐明。为了快速分析和鉴定聚糖，我们构建了一个血清糖组结构库，以帮助快速鉴定血清糖。用人血清糖蛋白的 N-聚糖作为标准，按照确切的结构（组成和连接）、液相色谱保留时间和精确质量进行编译，编入库中。库的开发依赖于高度可重复的纳升液相色谱-质谱保留时间。串联质谱和外切糖苷酶消化用于结构阐明。该库目前包含 300 多个条目，其中 50 个结构完全阐明，60 多个部分阐明。该数据库正在不断增长，并将用于快速鉴定未知生物样本中的聚糖。
