CHARGE REMOTE FRAGMENTATION IN ECD AND ETD

ECD 和 ETD 中的 CHARGE 远程碎片

• 批准号: 8170939
• 负责人: CHI-WEI LIN
• 金额: $ 0.81万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8170939
• 关键词: Amino Acids; Charge; Computer Retrieval of Information on Scientific Projects Database; Databases; Deposition; Dissociation; Electron Transport; Electrons; Funding; Grant; Hydrogen; Institution; Ions; Isomerism; Peptides; Positioning Attribute; Publishing; Research; Research Personnel; Resources; Side; Site; Source; United States National Institutes of Health; Vertebral column; synthetic peptide

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The primary N-C¿ bond cleavage by electron capture dissociation (ECD) or electron transfer dissociation (ETD) of a multiply charged peptide ion produces an even electron c ion and an odd electron z+ ion, the latter of which contains a radical which may initiate secondary fragmentations. These secondary fragmentations are all charge remote fragmentations (CRFs), because they do not involve the direct participation of a charged site. Secondary fragment ions generated by CRFs can be very useful for peptide structural analysis, as demonstrated by the utility of w-ions in isomer differentiation, but their presence may also complicate the spectral interpretation. In this study, secondary fragmentation of several synthetic peptides was studied by both ECD and ETD. In ECD, in addition to c and z+ ion formations, charge remote fragmentations (CRF) of z+ ions were abundant, resulting in internal fragment formation or partial/entire side chain losses from amino acids, sometimes several residues away from the backbone cleavage site, and to some extent multiple side chain losses. These secondary cleavages were postulated to be initiated by hydrogen abstraction at the ¿-, ¿-, or ¿-position of the amino acid side chain, after the initial backbone cleavage in ECD. In comparison, ETD generates fewer CRF fragments than ECD, possibly due to small energy deposition and stabilization of radicals in z+ ions by collisional cooling in ETD. This secondary cleavage study will facilitate ECD/ETD spectra interpretation, and help de novo sequencing and database searching. These results have been published in a recent J. Am. Soc. Mass Spectrom. article.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以出现在其他 CRISP 条目中 列出的机构是。 对于中心来说，它不一定是研究者的机构。 初级 N-C¿带电多肽离子通过电子捕获解离 (ECD) 或电子转移解离 (ETD) 进行键断裂，产生偶数电子 c 离子和奇数电子 z+ 离子，后者包含可能引发二次断裂的自由基。碎片都是电荷远程碎片 (CRF)，因为它们不涉及带电位点的直接参与，正如该实用程序所证明的那样，CRF 生成的次级碎片离子对于肽结构分析非常有用。 w 离子在异构体区分中的作用，但它们的存在也可能使光谱解释复杂化。 在本研究中，通过 ECD 和 ETD 研究了几种合成肽的二次断裂。在 ECD 中，除了 c 和 z+ 离子形成外，z+ 离子的电荷远程断裂 (CRF) 也很丰富，导致内部碎片形成或部分//。氨基酸的整个侧链损失，有时远离主链裂解位点的几个残基，并且在某种程度上，这些二次裂解被认为是由在主链裂解位点处的氢提取引发的。 ¿ -, ¿ -， 或者 - 氨基酸侧链的位置，在 ECD 中初始主链裂解后，ETD 产生的 CRF 片段比 ECD 少，这可能是由于 ETD 研究中通过碰撞冷却使 z+ 离子中的自由基稳定化。 ECD/ETD 光谱解释，并有助于从头测序和数据库搜索。这些结果已发表在 J. Am. 上。