Collision-Induced Dissociation of Lys-Lys Intramolecular Crosslinked Peptides
Collision-Induced Dissociation of Lys-Lys Intramolecular Crosslinked Peptides
复制标题
DOI：
10.1016/j.jasms.2008.11.009
复制
发表时间：
2009-04-01
影响因子：
3.2
通讯作者：
Gozzo, Fabio C.
中科院分区：
文献类型：
--
作者：
Iglesias, Amadeu H.;Santos, Luiz F. A.;Gozzo, Fabio C.
化学交联法的使用是一种吸引人的工具，在结构生物学的质谱学应用中显示出许多优点。然而，交联肽的正确分配仍然是。这是一个挑战，因为缺乏对结果物种的详细碎片化研究。在这项工作中，设计了分子内交联肽与琥珀酸二丁二亚胺(DSS)的裂解模式，利用一套通用的、类似于蛋白质交联实验中发现的物种的模型肽。这些肽含有一个乙酰化的N-末端，后面是一个随机的残基序列，其中包含由精氨酸分隔的两个赖氨酸残基。在交联化反应后，受控的胰酶消化产生分子内和分子间的交联肽。在本研究中，我们分析了基质辅助激光解吸/电离产生的多肽与DSS交联的裂解过程，其中两种赖氨酸都存在于同一多肽中。碎裂开始于多肽的线性部分，产生规则的b和y离子。一旦它到达分子的环状部分，观察到在随后的多肽键处或在多肽交联剂酰胺键处发生碎裂。如果肽的交联键被断裂，它就会以规则的修饰肽的形式碎裂，其中DSS的主干仍然附着在第一个赖氨酸上。这种碎片化模式类似于修饰多肽的碎片化，并且可以由使用DSS作为修改的普通自动搜索引擎来识别。另一方面，如果在肽键本身发生断裂，则观察到最后一个交联型赖氨酸的重排，并形成含有交联剂主链和赖氨酸(m/z 222)的产物离子。碎片离子的详细鉴定有助于开发专门用于交联肽的MS/MS数据分析的软件。(J am Soc MS Spectrm 2009，20,557-566)(C)2009，Elsevier Inc.代表美国质谱学学会出版
The use of chemical crosslinking is an attractive tool that presents many advantages in the application of mass spectrometry to structural biology. The correct assignment of crosslinked peptides, how-ever, is still. a challenge because of the lack of detailed fragmentation studies on resultant species. In this work, the fragmentation patterns of intramolecular crosslinked peptides with disuccinimidyl suberate (DSS) has been devised by using a set on versatile, model peptides that resemble species found in crosslinking experiments with proteins. These peptides contain an acetylated N-terminus followed by a random sequence of residues containing two lysine residues separated by an arginine. After the crosslinking reaction, controlled trypsin digestion yields both intra- and intermolecular crosslinked peptides. In the present study we analyzed the fragmentation of matrix-assisted laser desorption/ionization-generated peptides crosslinked with DSS in which both lysines are found in the same peptide. Fragmentation starts in the linear moiety of the peptide, yielding regular b and y ions. Once it reaches the cyclic portion of the molecule, fragmentation was observed to occur either at the following peptide bond or at the peptide crosslinker amide bond. If the peptide crosslinker bond is cleaved, it fragments as a regular modified peptide, in which the DSS backbone remains attached to the first lysine. This fragmentation pattern resembles the fragmentation of modified peptides and may be identified by common automated search engines using DSS as a modification. If, on the other hand, fragmentation happens at the peptide bond itself, rearrangement of the last crosslinked lysine is observed and a product ion containing the crosslinker backbone and lysine (m/z 222) is formed. The detailed identification of fragment ions can help the development of softwares devoted to the MS/MS data analysis of crosslinked peptides. (J Am Soc Mass Spectrom 2009, 20, 557-566) (C) 2009 Published by Elsevier Inc. on behalf of American Society for Mass Spectrometry