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  • Accepted Manuscript: Solution structure of a europium–nicotianamine complex supports that phytosiderophores bind lanthanides
Title: Solution structure of a europium–nicotianamine complex supports that phytosiderophores bind lanthanides
We report the solution structure of a europium-nicotianamine complex predicted from ab initio molecular dynamics simulations with density functional theory. Emission and excitation spectroscopy show that the Eu 3+ coordination environment changes in the presence of nicotianamine, suggesting complex formation, such as what is seen for the Eu 3+ –nicotianamine complex structure predicted from computation. We modeled Eu 3+ –ligand complexes with explicit water molecules in periodic boxes, effectively simulating the solution phase. Our simulations consider possible chemical events ( e.g. coordination bond formation, protonation state changes, charge transfers), as well as ligand flexibility and solvent rearrangements. Our computational approach correctly predicts the solution structure of a Eu 3+ –ethylenediaminetetraacetic acid complex within 0.05 Å of experimentally measured values, backing the fidelity of the predicted solution structure of the Eu 3+ –nicotianamine complex. Emission and excitation spectroscopy measurements were also performed on the well-known Eu 3+ –ethylenediaminetetraacetic acid complex to validate our experimental methods. The electronic structure of the Eu 3+ –nicotianamine complex is analyzed to describe the complexes in greater detail. Nicotianamine is a metabolic precursor of, and structurally very similar to, phytosiderophores, which are responsible for the uptake of metals in plants. Although knowledge that nicotianamine binds europium more » does not determine how plants uptake rare earths from the environment, it strongly supports that phytosiderophores bind lanthanides. « less
Authors:
; ; ; ;
Award ID(s):
1800392
Publication Date:
NSF-PAR ID:
10277336
Journal Name:
Physical Chemistry Chemical Physics
Volume:
23
Issue:
7
Page Range or eLocation-ID:
4287 to 4299
ISSN:
1463-9076
Sponsoring Org:
National Science Foundation
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