Comparative Dissociation of Peptide Polyanions by Electron Impact and Photo-Induced Electron Detachment
Comparative Dissociation of Peptide Polyanions by Electron Impact and Photo-Induced Electron Detachment
复制标题
DOI：
10.1016/j.jasms.2010.01.015
复制
发表时间：
2010-04-01
影响因子：
3.2
通讯作者：
Dugourd, Philippe
中科院分区：
文献类型：
--
作者：
Larraillet, Vincent;Vorobyev, Aleksey;Dugourd, Philippe
我们分别在傅里叶变换和线性离子阱质谱仪上比较了多去质子肽的电子分离解离（EDD）和电子光分离解离（EPD）产生的产物离子质谱。两种方法，EDD和EPD，都涉及电子发射诱导的自由基氧化物质的形成，从一个多去质子化的前体肽。产物离子质谱主要显示c - α - c键断裂导致的主链断裂产生的碎片离子，产生a和x离子。来自n - c - α主键断裂的碎片离子也被观察到，特别是通过EPD。虽然EDD和EPD方法都是通过电子发射产生电荷还原的自由基阴离子中间体，但产物的离子丰度分布却有很大的不同。这两个过程似乎都是由自由基（中性和阳离子自由基）的定位和重组引发的。因此，EPD产物离子主要在色氨酸和组氨酸残基附近形成，而在EDD中，主链上的负电荷溶剂化位点似乎最有利于附近的键解离。（J Am Soc质谱，2010,21,670-680）(C) 2010由Elsevier Inc.代表美国质谱学会出版
We compare product-ion mass spectra produced by electron detachment dissociation (EDD) and electron photodetachment dissociation (EPD) of multi-deprotonated peptides on a Fourier transform and a linear ion trap mass spectrometer, respectively. Both methods, EDD and EPD, involve the electron emission-induced formation of a radical oxidized species from a multi-deprotonated precursor peptide. Product-ion mass spectra display mainly fragment ions resulting from backbone cleavages of C-alpha-C bond ruptures yielding a and x ions. Fragment ions originating from N-C-alpha backbone bond cleavages are also observed, in particular by EPD. Although EDD and EPD methods involve the generation of a charge-reduced radical anion intermediate by electron emission, the product ion abundance distributions are drastically different. Both processes seem to be triggered by the location and the recombination of radicals (both neutral and cation radicals). Therefore, EPD product ions are predominantly formed near tryptophan and histidine residues, whereas in EDD the negative charge solvation sites on the backbone seem to be the most favorable for the nearby bond dissociation. (J Am Soc Mass Spectrom 2010, 21, 670-680) (C) 2010 Published by Elsevier Inc. on behalf of American Society for Mass Spectrometry