Leroux, JulietteJulietteLerouxChesnel Jean-yvesOrtiz Mahecha, CarlosCarlosOrtiz MahechaNair, AarathiAarathiNairOostenrijk, BartBartOostenrijkPille, LauraLauraPilleTrinter, FlorianFlorianTrinterSchwob, LucasLucasSchwobBari, SadiaSadiaBari2025-01-312025-01-312025-01-05Chemistry - a European journal 31 (10): e202403665 (2025)https://tore.tuhh.de/handle/11420/53658Gas-phase near-edge X-ray absorption mass spectrometry (NEXAMS) was employed at the carbon and oxygen K-edges to probe the influence of a single water molecule on the protonated phosphotyrosine molecule. The results of the photodissociation experiments revealed that the water molecule forms two bonds, with the phosphate group and another chemical group. By comparing the NEXAMS spectra at the carbon and oxygen K-edges with density functional theory calculations, we attributed the electronic transitions responsible for the observed resonances, especially the transitions due to the presence of the water molecule. We showed that the water molecule leads to a specific spectral feature in the partial ion yield of hydrated fragments at 536.4 eV. Moreover, comparing the NEXAMS spectra with the calculated structures allowed us to identify three possible structures for singly hydrated phosphotyrosine that agree with the observed fragmentation and resonances.en1521-3765202510Wileyhttps://creativecommons.org/licenses/by/4.0/Biomolecules | Density functional theory | Nanosolvation | Soft X-ray spectroscopyNatural Sciences and Mathematics::539: Matter; Molecular Physics; Atomic and Nuclear physics; Radiation; Quantum PhysicsNatural Sciences and Mathematics::543: AnalyticNatural Sciences and Mathematics::541: Physical; Theoretical::541.3: Physical ChemistryJournal Articlehttps://doi.org/10.15480/882.1454410.1002/chem.20240366510.15480/882.14544Journal Article