通过与亚稳原子相互作用实现磷酸化单电荷肽离子的碎裂

Fragmentation of phosphorylated and singly charged peptide ions via interaction with metastable atoms.

作者信息

Berkout Vadym D, Doroshenko Vladimir M

机构信息

MassTech, Inc., Columbia, MD 21046.

出版信息

Int J Mass Spectrom. 2008 Dec 1;278(2-3):150-157. doi: 10.1016/j.ijms.2008.04.019.

Fragmentation of phosphorylated peptide ions via interaction with electronically excited metastable argon atoms was studied in a linear trap - time-of-flight mass spectrometer. Doubly charged ions of phosphorylated peptides from an Enolase digest were produced by electrospray ionization and subjected to a metastable atom beam in the linear trap. The metastable argon atoms were generated using a glow-discharge source. An intensive series of c- and z- ions were observed in all cases, with the phosphorylation group intact. The formation of molecular radical cations with reduced charge indicated that an electron transfer from a highly excited metastable state of argon to the peptide cation occurred. Additionally, singly charged Bradykinin, Substance P and Fibrinopeptide A molecular ions were fragmented via interaction with electronically excited metastable helium atoms. The fragmentation mechanism was different in this case and involved Penning ionization.

在线性阱-飞行时间质谱仪中研究了磷酸化肽离子与电子激发的亚稳态氩原子相互作用导致的碎裂。来自烯醇化酶消化产物的磷酸化肽的双电荷离子通过电喷雾电离产生，并在线性阱中受到亚稳态原子束的作用。亚稳态氩原子使用辉光放电源产生。在所有情况下都观察到了一系列密集的c离子和z离子，磷酸化基团保持完整。电荷减少的分子自由基阳离子的形成表明发生了从氩的高激发亚稳态到肽阳离子的电子转移。此外，单电荷的缓激肽、P物质和纤维蛋白肽A分子离子通过与电子激发的亚稳态氦原子相互作用而碎裂。在这种情况下，碎裂机制不同，涉及彭宁电离。