2. Academic Validation
  3. l-Cysteine Modified by S-Sulfation: Consequence on Fragmentation Processes Elucidated by Tandem Mass Spectrometry and Chemical Dynamics Simulations

l-Cysteine Modified by S-Sulfation: Consequence on Fragmentation Processes Elucidated by Tandem Mass Spectrometry and Chemical Dynamics Simulations

  • J Phys Chem A. 2019 May 2;123(17):3685-3696. doi: 10.1021/acs.jpca.9b01779.
Veronica Macaluso 1,  Debora Scuderi 2,  Maria Elisa Crestoni 3,  Simonetta Fornarini 3,  Davide Corinti 3,  Enzo Dalloz 2 3,  Emilio Martinez-Nunez 4,  William L Hase 5,  Riccardo Spezia 1 6
Affiliations

Affiliations

  • 1 LAMBE, Univ Evry, CNRS, CEA, Université Paris-Saclay , 91025 Évry , France.
  • 2 LCP, Laboratoire de Chimie Physique , Université Paris-Sud, Bat. 349, CNRS UMR8000 , 15 rue Georges Clemenceau , 91405 Orsay Cedex, France.
  • 3 Dipartimento di Chimica e Tecnologie del Farmaco , Università degli Studi di Roma La Sapienza , P.le A. Moro 5 , 00185 Roma , Italy.
  • 4 Departamento de Química Física, Facultade de Química, Campus Vida , Universidade de Santiago de Compostela , 15782 Santiago de Compostela , Spain.
  • 5 Department of Chemistry and Biochemistry , Texas Tech University , Lubbock , Texas 79409 , United States.
  • 6 CNRS, Laboratoire de Chimie Théorique, LCT , Sorbonne Université , 4, Place Jussieu , 75252 Paris Cedex 05, France.
PMID: 30945861 DOI: 10.1021/acs.jpca.9b01779
Abstract

Low-energy collision-induced dissociation (CID) of deprotonated l-cysteine S-sulfate, [cysS-SO3]-, delivered in the gas phase by electrospray ionization, has been found to provide a means to form deprotonated l-cysteine sulfenic acid, which is a fleeting intermediate in biological media. The reaction mechanism underlying this process is the focus of the present contribution. At the same time, Other novel species are formed, which were not observed in previous experiments. To understand fragmentation pathways of [cysS-SO3]-, reactive chemical dynamics simulations coupled with a novel algorithm for automatic determination of intermediates and transition states were performed. This approach has allowed the identification of the mechanisms involved and explained the experimental fragmentation pathways. Chemical dynamics simulations have shown that a roaming-like mechanism can be at the origin of l-cysteine sulfenic acid.

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