IRMPD spectroscopy of deprotonated selenocysteine - The 21st proteinogenic amino acid

IF 1.6 3区化学 Q3 PHYSICS, ATOMIC, MOLECULAR & CHEMICAL International Journal of Mass Spectrometry Pub Date : 2024-08-10 DOI:10.1016/j.ijms.2024.117322

Davide Corinti , Giel Berden , Jos Oomens , Bruno Martinez-Haya , Simonetta Fornarini , Maria Elisa Crestoni

{"title":"IRMPD spectroscopy of deprotonated selenocysteine - The 21st proteinogenic amino acid","authors":"Davide Corinti , Giel Berden , Jos Oomens , Bruno Martinez-Haya , Simonetta Fornarini , Maria Elisa Crestoni","doi":"10.1016/j.ijms.2024.117322","DOIUrl":null,"url":null,"abstract":"<div><p>The effect of deprotonation on the structure and stability of the 21st proteinogenic amino acid selenocysteine, generated as bare deprotonated species by electrospray ionization, has been investigated by infrared multiple photon dissociation (IRMPD) spectroscopy over an extended frequency range (700-3600 cm<sup>−1</sup>), encompassing both the fingerprint and X–H (X = C, N, O) stretching ranges. IRMPD spectra, interpreted by anharmonic DFT calculations, provide evidence of a thermally averaged ion population of two types of low-lying canonical conformers deprotonated at the selenol (Se–H) group and involved in different H-bonding motifs.</p><p>The broadened and diffuse band structures observed in the H-stretching range are well interpreted by Born-Oppenheimer molecular dynamics computations that provide a valuable description of the flexible backbone arrangements of Sec and of the proton sharing dynamics in the Se–HO and Se–HN moieties.</p><p>Other prototropic isomers, deprotonated at the carboxylic group or with a zwitterionic structure, should not be significantly populated, according to their higher free energy and calculated IR spectra inconsistent with experimental evidence.</p></div>","PeriodicalId":338,"journal":{"name":"International Journal of Mass Spectrometry","volume":"505 ","pages":"Article 117322"},"PeriodicalIF":1.6000,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1387380624001337/pdfft?md5=3ca15d27266b9fd3e1934f5a82a7eb7c&pid=1-s2.0-S1387380624001337-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Mass Spectrometry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1387380624001337","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, ATOMIC, MOLECULAR & CHEMICAL","Score":null,"Total":0}

引用次数: 0

Abstract

The effect of deprotonation on the structure and stability of the 21st proteinogenic amino acid selenocysteine, generated as bare deprotonated species by electrospray ionization, has been investigated by infrared multiple photon dissociation (IRMPD) spectroscopy over an extended frequency range (700-3600 cm⁻¹), encompassing both the fingerprint and X–H (X = C, N, O) stretching ranges. IRMPD spectra, interpreted by anharmonic DFT calculations, provide evidence of a thermally averaged ion population of two types of low-lying canonical conformers deprotonated at the selenol (Se–H) group and involved in different H-bonding motifs.

The broadened and diffuse band structures observed in the H-stretching range are well interpreted by Born-Oppenheimer molecular dynamics computations that provide a valuable description of the flexible backbone arrangements of Sec and of the proton sharing dynamics in the Se–HO and Se–HN moieties.

Other prototropic isomers, deprotonated at the carboxylic group or with a zwitterionic structure, should not be significantly populated, according to their higher free energy and calculated IR spectra inconsistent with experimental evidence.

Abstract Image

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

去质子化硒代半胱氨酸的 IRMPD 光谱 - 第 21 种蛋白质氨基酸

红外多光子解离（IRMPD）光谱法研究了电喷雾电离产生的第 21 种蛋白源氨基酸硒代半胱氨酸的去质子化对其结构和稳定性的影响，这种氨基酸作为裸去质子化物种，其频率范围较广（700-3600 cm-1），包括指纹和 X-H（X = C、N、O）伸展范围。通过非谐波 DFT 计算对 IRMPD 光谱进行解释，可以证明在硒醇（Se-H）基团上去质子化并参与不同 H 键结构的两种低洼典型构象的热平均离子群。Born-Oppenheimer 分子动力学计算很好地解释了在 H 伸缩范围内观察到的拓宽和扩散带结构，对 Sec 的柔性骨架排列以及 Se-HO 和 Se-HN 分子中的质子共享动力学提供了有价值的描述。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

International Journal of Mass Spectrometry 物理-光谱学

CiteScore

3.60

自引率

5.60%

发文量

145

审稿时长

71 days

期刊介绍： The journal invites papers that advance the field of mass spectrometry by exploring fundamental aspects of ion processes using both the experimental and theoretical approaches, developing new instrumentation and experimental strategies for chemical analysis using mass spectrometry, developing new computational strategies for data interpretation and integration, reporting new applications of mass spectrometry and hyphenated techniques in biology, chemistry, geology, and physics. Papers, in which standard mass spectrometry techniques are used for analysis will not be considered. IJMS publishes full-length articles, short communications, reviews, and feature articles including young scientist features.

期刊最新文献

Graphical abstract TOC Graphical abstract TOC Editorial Board Editorial Board Contents continued