Webber Nathaniel, He Yi, Reilly James P
Department of Chemistry, Indiana University, Bloomington, IN, 47405, USA.
J Am Soc Mass Spectrom. 2014 Feb;25(2):196-203. doi: 10.1007/s13361-013-0762-2. Epub 2013 Dec 6.
Twenty singly-charged dipeptide ions with N-terminal arginine were photodissociated using 157 nm light in both a linear ion-trap mass spectrometer and a MALDI-TOF-TOF mass spectrometer. Analogous to previous work on dipeptides containing C-terminal arginine, this set of samples enabled insights into the photofragmentation propensities associated with individual residues. In addition to familiar products such as a-, d-, and immonium ions, m2 and m2+13 ions were also observed. Certain side chains tended to cleave between their β and γ carbons without necessarily forming d- or w-type ions, and a few other ions were produced by the high-energy fragmentation of multiple bonds.
在线性离子阱质谱仪和基质辅助激光解吸电离飞行时间串联质谱仪中，使用157 nm光对20个带有N端精氨酸的单电荷二肽离子进行了光解离。与之前对含有C端精氨酸的二肽的研究类似，这组样品有助于深入了解与各个残基相关的光碎片化倾向。除了常见的产物，如α-、δ-和亚铵离子外，还观察到了m2和m2 + 13离子。某些侧链倾向于在其β和γ碳之间断裂，而不一定形成δ-或ω-型离子，还有一些其他离子是由多键的高能碎片化产生的。
