Lermyte Frederik, Williams Jonathan P, Brown Jeffery M, Martin Esther M, Sobott Frank
Biomolecular and Analytical Mass Spectrometry group, Department of Chemistry, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium.
J Am Soc Mass Spectrom. 2015 Jul;26(7):1068-76. doi: 10.1007/s13361-015-1124-z. Epub 2015 Apr 11.
Non-dissociative charge reduction, typically considered to be an unwanted side reaction in electron transfer dissociation (ETD) experiments, can be enhanced significantly in order to reduce the charge state of intact protein complexes to as low as 1+ on a commercially available Q-IM-TOF instrument. This allows for the detection of large complexes beyond 100,000 m/z, while at the same time generating top-down ETD fragments, which provide sequence information from surface-exposed parts of the folded structure. Optimization of the supplemental activation has proven to be crucial in these experiments and the charge-reduced species are most likely the product of both proton transfer (PTR) and non-dissociative electron transfer (ETnoD) reactions that occur prior to the ion mobility cell. Applications of this approach range from deconvolution of complex spectra to the manipulation of charge states of gas-phase ions.
非解离性电荷减少通常被认为是电子转移解离（ETD）实验中不希望出现的副反应，但在商用Q-IM-TOF仪器上，可以显著增强这种反应，以便将完整蛋白质复合物的电荷状态降低至低至1+。这使得能够检测超过100,000 m/z的大型复合物，同时生成自上而下的ETD片段，这些片段提供来自折叠结构表面暴露部分的序列信息。在这些实验中，补充激活的优化已被证明至关重要，电荷减少的物种很可能是在离子迁移池之前发生的质子转移（PTR）和非解离性电子转移（ETnoD）反应的产物。这种方法的应用范围从复杂光谱的去卷积到气相离子电荷状态的操纵。
