TY - JOUR
AU - Mudryk, Karen
AU - Lee, Chin
AU - Tomaník, Lukáš
AU - Malerz, Sebastian
AU - Trinter, Florian
AU - Hergenhahn, Uwe
AU - Neumark, Daniel M.
AU - Slavicek, Petr
AU - Bradforth, Stephen
AU - Winter, Bernd
TI - How Does Mg<sup>2+</sup><sub>(aq)</sub> Interact with ATP<sub>(aq)</sub>? Biomolecular Structure through the Lens of Liquid-Jet Photoemission Spectroscopy
JO - Journal of the American Chemical Society
VL - 146
IS - 23
SN - 0002-7863
CY - Washington, DC
PB - ACS Publications
M1 - PUBDB-2024-04728
SP - 16062-16075
PY - 2024
N1 - Open Access
AB - Liquid-jet photoemission spectroscopy (LJ-PES) allows for a direct probing of electronic structure in aqueous solutions. We show the applicability of the approach to biomolecules in a complex environment, exploring site-specific information on the interaction of adenosine triphosphate in the aqueous phase (ATP<sub>(aq)</sub>) with magnesium (Mg<sup>2+</sup><sub>(aq)</sub>), highlighting the synergy brought about by the simultaneous analysis of different regions in the photoelectron spectrum. In particular, we demonstrate intermolecular Coulombic decay (ICD) spectroscopy as a new and powerful addition to the arsenal of techniques for biomolecular structure investigation. We apply LJ-PES assisted by electronic-structure calculations to study ATP<sub>(aq)</sub> solutions with and without dissolved Mg<sup>2+</sup>. Valence photoelectron data reveal spectral changes in the phosphate and adenine features of ATP<sub>(aq)</sub> due to interactions with the divalent cation. Chemical shifts in Mg 2p, Mg 2s, P 2p, and P 2s core-level spectra as a function of the Mg<sup>2+</sup>/ATP concentration ratio are correlated to the formation of [Mg(ATP) <sub>2</sub>]<sup>6−</sup><sub>(aq)</sub>, [MgATP]<sup>2−</sup><sub>(aq)</sub>, and [Mg<sub>2</sub>ATP]<sub>(aq)</sub> complexes, demonstrating the element sensitivity of the technique to Mg<sup>2+</sup>–phosphate interactions. The most direct probe of the intermolecular interactions between ATP<sub>(aq)</sub> and Mg<sup>2+</sup><sub>(aq)</sub> is delivered by the emerging ICD electrons following ionization of Mg 1s electrons. ICD spectra are shown to sensitively probe ligand exchange in the Mg<sup>2+</sup>–ATP<sub>(aq)</sub> coordination environment. In addition, we report and compare P 2s data from ATP<sub>(aq)</sub> and adenosine mono- and diphosphate (AMP<sub>(aq)</sub> and ADP<sub>(aq)</sub>, respectively) solutions, probing the electronic structure of the phosphate chain and the local environment of individual phosphate units in ATP<sub>(aq)</sub>. Our results provide a comprehensive view of the electronic structure of ATP<sub>(aq)</sub> and Mg<sup>2+</sup>–ATP<sub>(aq)</sub> complexes relevant to phosphorylation and dephosphorylation reactions that are central to bioenergetics in living organisms.
LB - PUB:(DE-HGF)16
C6 - pmid:38802319
UR - <Go to ISI:>//WOS:001234460800001
DO - DOI:10.1021/jacs.4c03174
UR - https://bib-pubdb1.desy.de/record/610905
ER -