申请人:Reid Gavin
公开号:US20060094121A1
公开(公告)日:2006-05-04
The invention provides methods, reagents and kits for amino acid, peptide and protein identification, differential quantitation and for the analysis of post translational modification and cross-linking status, comprising: derivatizing a mixture of amino acids peptides or proteins, to form at least one amino acid peptide or protein containing a fixed-charge ion, other than at the C-terminal or N-terminal end thereof; introducing the mixture of amino acids peptides or proteins containing the fixed charge derivatized amino acid peptide or protein to a mass spectrometer; passing the mixture of amino acids peptides or proteins containing the fixed charge derivatized amino acid peptide or protein through a first mass resolving spectrometer to select precursor protein or peptide ions having a first desired mass-to-charge ratio; subjecting the precursor ions of the first mass to charge ratio to dissociation to form a product ion having a second mass-to-charge ratio that is characteristic of a fragmentation occurring at a site adjacent to the fixed charge; and detecting the product ions having the second mass-to-charge ratio. The product ion having the second mass-to-charge ratio may be either a product ion formed by neutral loss of the fixed charge from the precursor ion, or a product ion formed by charged loss of the fixed charge from the precursor ion.
本发明提供了用于氨基酸、肽和蛋白质鉴定、差异定量以及后转录后修饰和交联状态分析的方法、试剂和试剂盒,包括:将混合的氨基酸、肽或蛋白质衍生化,形成至少一个含有固定电荷离子的氨基酸、肽或蛋白质,除了其C-末端或N-末端;将含有固定电荷衍生化氨基酸、肽或蛋白质的混合物引入质谱仪;通过第一质量分辨质谱仪对含有固定电荷衍生化氨基酸、肽或蛋白质的混合物进行筛选,以选择具有第一所需质荷比的前体蛋白质或肽离子;将第一质荷比的前体离子进行解离,形成具有第二质荷比的产物离子,其特征是在固定电荷相邻的位置发生了碎片化;检测具有第二质荷比的产物离子。第二质荷比的产物离子可能是由前体离子失去固定电荷形成的产物离子,也可能是由带电失去固定电荷的前体离子形成的产物离子。