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Phosphorus Kβ X-ray emission spectroscopy detects non-covalent interactions of phosphate biomolecules in situ.

ABSTRACT: Phosphorus is ubiquitous in biochemistry, being found in the phosphate groups of nucleic acids and the energy-transferring system of adenine nucleotides (e.g. ATP). Kβ X-ray emission spectroscopy (XES) of phosphorus has been largely unexplored, with no previous applications to biomolecules. Here, the potential of P Kβ XES to study phosphate-containing biomolecules, including ATP and NADPH, is evaluated, as is the application of the technique to aqueous solution samples. P Kβ spectra offer a detailed picture of phosphate valence electronic structure, reporting on subtle non-covalent effects, such as hydrogen bonding and ionic interactions, that are key to enzymatic catalysis. Spectral features are interpreted using density functional theory (DFT) calculations, and potential applications to the study of biological energy conversion are highlighted.

SUBMITTER: Mathe Z

PROVIDER: S-EPMC8188515 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Phosphorus Kβ X-ray emission spectroscopy detects non-covalent interactions of phosphate biomolecules in situ.

Mathe Zachary Z McCubbin Stepanic Olivia O Peredkov Sergey S DeBeer Serena S

Chemical science 20210429 22

Phosphorus is ubiquitous in biochemistry, being found in the phosphate groups of nucleic acids and the energy-transferring system of adenine nucleotides (e.g. ATP). Kβ X-ray emission spectroscopy (XES) of phosphorus has been largely unexplored, with no previous applications to biomolecules. Here, the potential of P Kβ XES to study phosphate-containing biomolecules, including ATP and NADPH, is evaluated, as is the application of the technique to aqueous solution samples. P Kβ spectra offer ...[more]

PMID: 34168842

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