Electron transfer dissociation mass spectrometry of acidic phosphorylated peptides cationized with trivalent praseodymium.
Electron transfer dissociation mass spectrometry of acidic phosphorylated peptides cationized with trivalent praseodymium.
复制标题
用三价镨阳离子化的酸性磷酸化肽的电子转移解离质谱法。
DOI：
10.1002/jms.4291
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Cassady,CarolynJ
中科院分区：
文献类型：
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作者：
Commodore,JulietteJ;Cassady,CarolynJ
用稀土离子Pr(III)研究了27个生物和模拟高酸性磷酸肽的金属离子形成和电子转移解离(ETD)。所有研究的磷酸肽都是通过电喷雾电离(ESI)从金属离子中形成的，可以用ETD进行研究，以获得丰富的序列信息。形成的离子有[M++Pr·−·H]2+、[M++Pr]3+和[M++Pr++TH]4+。所有链长为7个或更多残基的生物磷酸肽都会产生[M++Pr]3+。对于生物磷酸肽，[M~(++)Pr]~(3+)比[M~(++)Pr-H]~(2+)经历更多的骨架切割，在某些情况下，出现全序列覆盖。酸性模型磷酸化六肽和八肽由丙氨酸残基和一个磷酸化残基组成，经ESI分析，完全形成[M++Pr-H]2+。通过[M~(++)Pr-H]~(2+)的ETD获得了有限的序列信息，只产生了金属产物离子。对于两个生物磷酸肽，观察到[M++Pr++[H]4+]4+，这可能是由于存在至少一个残基，具有高度碱性的侧链，有利于额外的质子加成。对于模型磷酸肽，当磷酸化残基在序列的中间时，比在N-末端或C-末端出现更多的序列覆盖。由ESI形成的金属前驱体离子的ETD专门为生物磷肽生成金属和非金属C-和Z-离子，而为模型磷肽生成金属C-离子、Z-离子和少量Y-离子。大多数产物离子含有磷酸化残基，表明金属离子主要结合在去质子化的磷酸基团上。这项研究的结果表明，ETD是一种很有前途的工具，通过与Pr(III)以及所有非放射性稀土金属离子的金属加合，对高度酸性的磷酸化肽进行测序。
The lanthanide ion praseodymium, Pr(III), was employed to study metallated ion formation and electron transfer dissociation (ETD) of 27 biological and model highly acidic phosphopeptides. All phosphopeptides investigated form metallated ions by electrospray ionization (ESI) that can be studied by ETD to yield abundant sequence information. The ions formed are [M + Pr − H]2+, [M + Pr]3+, and [M + Pr + H]4+. All biological phosphopeptides with a chain length of seven or more residues generate [M + Pr]3+. For biological phosphopeptides, [M + Pr]3+undergoes more backbone cleavage by ETD than [M + Pr – H]2+and, in some cases, full sequence coverage occurs. Acidic model phosphorylated hexa‐peptides and octa‐peptides, composed of alanine residues and one phosphorylated residue, form exclusively [M + Pr – H]2+by ESI. Limited sequence information is obtained by ETD of [M + Pr – H]2+with only metallated product ions being generated. For two biological phosphopeptides, [M + Pr + H]4+is observed and may be due to the presence of at least one residue with a highly basic side chain that facilitates the addition of an extra proton. For the model phosphopeptides, more sequence coverage occurs when the phosphorylated residue is in the middle of the sequence than at either the N‐ or C‐terminus. ETD of the metallated precursor ions formed by ESI generates exclusively metallated and nonmetallated c‐ and z‐ions for the biological phosphopeptides, while metallated c‐ions, z‐ions, and a few y‐ions form for the model phosphopeptides. Most of the product ions contain the phosphorylated residue indicating that the metal ion binds predominantly at the deprotonated phosphate group. The results of this study indicate that ETD is a promising tool for sequencing highly acidic phosphorylated peptides by metal adduction with Pr (III) and, by extension, all nonradioactive lanthanide metal ions.