Electron photodetachment dissociation of DNA polyanions in a quadrupole ion trap mass spectrometer
Electron photodetachment dissociation of DNA polyanions in a quadrupole ion trap mass spectrometer
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DOI：
10.1021/ac060753p
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发表时间：
2006-09-15
影响因子：
7.4
通讯作者：
Dugourd, Philippe
中科院分区：
文献类型：
--
作者：
Gabelica, Valerie;Tabarin, Thibault;Dugourd, Philippe
在此，我们探讨了照射DNA聚阴离子存储在四极离子阱质谱仪与光学参量振荡器激光之间的250和285 nm的影响。我们研究了DNA 6-20聚体单链和12碱基对双链。在所有情况下，激光照射导致电子从多电荷DNA阴离子脱离。电子光剥离效率直接取决于链中鸟嘌呤的数量，并且在260和275 nm之间观察到最大效率。随后的碰撞诱导解离（CID）的自由基阴离子产生的电子光剥离的结果在广泛的碎裂。除了中性丢失外，大量来自w，d，a.，和z.离子系列得到，与常规CID中观察到的W和（a-基）离子系列形成对比。这种技术的主要优点，创造了电子光剥离解离（EPD）是没有内部片段，结合良好的序列覆盖。因此，EPD是一种非常有前途的寡核苷酸从头测序方法。还预期核酸的EPD给出特定的自由基诱导的链裂解，并保留其他脆弱键，包括非共价键。实际上，对DNA发夹和双链的初步结果表明，EPD也可用于探测核酸中的分子内和分子间相互作用。
We hereby explore the effects of irradiating DNA polyanions stored in a quadrupole ion trap mass spectrometer with an optical parametric oscillator laser between 250 and 285 nm. We studied DNA 6-20-mer single strands and 12-base pair double strands. In all cases, laser irradiation causes electron detachment from the multiply charged DNA anions. Electron photodetachment efficiency directly depends on the number of guanines in the strand, and maximum efficiency is observed between 260 and 275 nm. Subsequent collision-induced dissociation ( CID) of the radical anions produced by electron photodetachment results in extensive fragmentation. In addition to neutral losses, a large number of fragments from the w, d, a., and z. ion series are obtained, contrasting with the w and (a-base) ion series observed in regular CID. The major advantage of this technique, coined electron photodetachment dissociation (EPD) is the absence of internal fragments, combined with good sequence coverage. EPD is therefore a highly promising approach for de novo sequencing of oligonucleotides. EPD of nucleic acids is also expected to give specific radical-induced strand cleavages, with conservation of other fragile bonds, including noncovalent bonds. In effect, preliminary results on a DNA hairpin and on double strands suggest that EPD could also be used to probe intra- and intermolecular interactions in nucleic acids.