Gas-phase peptide sequencing by TEMPO-mediated radical generation
Gas-phase peptide sequencing by TEMPO-mediated radical generation
复制标题
DOI：
10.1039/b904115j
复制
发表时间：
2009-01-01
期刊：
影响因子：
4.2
通讯作者：
Oh, Han Bin
中科院分区：
文献类型：
--
作者：
Lee, Minhee;Kang, Minhyuck;Oh, Han Bin
2-[（2,2,6,6-四甲基胡椒碱-1-酰基）甲基]苯甲酸（TEMPO-Bz）共轭肽阳离子通过将tempo衍生的前体1连接到n端氨基或赖氨酸侧链上而碰撞激活，导致自由基的形成。随后对自由基阳离子的串联质谱分析显示，与电子捕获解离（ECD）或电子转移解离（ETD）观察到的方式相同，奇数电子肽主链解离。例如，a-、x-或z型离子是主要的碎片，二硫键很容易断裂。TEMPO-FRIPS（自由基启动肽测序）也适用于表征单质子化肽，而ECD或ETD中只有双质子化或高度质子化的阳离子响应。TEMPO-FRIPS方法也具有通用性，因为它可以用于任何类型的串联质谱仪。
Collisional activation of 2-[(2,2,6,6-tetramethylpiperidin-1-yloxy)methyl]benzoic acid (TEMPO-Bz)-conjugated peptide cations, prepared by attaching a TEMPO-derived precursor 1 to an N-terminal amino group or a lysine side chain, resulted in the formation of radical species. The subsequent tandem mass spectrometry on the radical cations exhibited odd-electron peptide backbone dissociations in the same manner as that observed by electron capture dissociation (ECD) or electron transfer dissociation (ETD). For example, a-, x-, or z-types of ions were major fragments and the disulfide bond was readily cleaved. The TEMPO-FRIPS (free radical initiated peptide sequencing) was also applicable to characterizing even singly protonated peptides, in contrast to ECD or ETD in which only doubly or highly protonated cations are responsive. The TEMPO-FRIPS approach also has universality in that it can be used in any type of a tandem mass spectrometer.