Multiple Ionization of Free Ubiquitin Molecular Ions in Extreme Ultraviolet Free‐Electron Laser Pulses. (25th July 2016)

• Record Type: Journal Article
• Authors: Schlathölter, Thomas; Reitsma, Geert; Egorov, Dmitrii; Gonzalez‐Magaña, Olmo; Bari, Sadia; Boschman, Leon; Bodewits, Erwin; Schnorr, Kirsten; Schmid, Georg; Schröter, Claus Dieter; Moshammer, Robert; Hoekstra, Ronnie
• Is Part Of: Angewandte Chemie. Volume 128:Number 36(2016)
• Page Start: 10899
• Page End: 10903
• Publication Date: 2016-07-25
• Subjects: Freie-Elektronen-Laser -- Massenspektrometrie -- Mehrphotonenionisation -- Photoionisation -- Proteine; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201605335
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: The fragmentation of free tenfold protonated ubiquitin in intense 70 femtosecond pulses of 90 eV photons from the FLASH facility was investigated. Mass spectrometric investigation of the fragment cations produced after removal of many electrons revealed fragmentation predominantly into immonium ions and related ions, with yields increasing linearly with intensity. Ionization clearly triggers a localized molecular response that occurs before the excitation energy equilibrates. Consistent with this interpretation, the effect is almost unaffected by the charge state, as fragmentation of sixfold deprotonated ubiquitin leads to a very similar fragmentation pattern. Ubiquitin responds to EUV multiphoton ionization as an ensemble of small peptides.