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Updated: Jul 1, 2026
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Europium Coordination Structure in Peptide Complexes Resolved with Simulation and X-ray Absorption Spectroscopy
Sina Chiniforoush1, Shelly D Kelly2, Oksana Fizer3
1Department of Chemical and Materials Engineering, University of Nevada, Reno, Reno, Nevada 89557, United States.
Researchers developed lanthanide binding cyclic peptides (LBCPs) with selectivity for middle lanthanides. Combining molecular dynamics (MD) simulations and extended X-ray absorption fine structure (EXAFS) spectroscopy resolved europium complex structures.
Area of Science:
- Coordination chemistry
- Bioinorganic chemistry
- Analytical chemistry
Background:
- Understanding lanthanide-ligand complex structures is key to ligand selectivity.
- Lanthanide binding cyclic peptides (LBCPs) have shown selectivity for middle lanthanides.
- Accurate structural determination of these complexes in solution is challenging.
Purpose of the Study:
- To report micromolar affinity in a europium-LBCP complex.
- To resolve the coordination structure of europium complexes with two LBCPs.
- To validate a combined approach of molecular simulation and EXAFS for structural analysis.
Main Methods:
- Design and synthesis of lanthanide binding cyclic peptides (LBCPs).
- Experimental measurement of extended X-ray absorption fine structure (EXAFS) spectra for europium complexes.
- Molecular dynamics (MD) simulations to generate ensemble-average spectra.
- Comparison of experimental EXAFS spectra with computationally derived and model-based spectra.
Main Results:
- Micromolar affinity was observed for a europium-LBCP complex.
- Agreement was found between experimentally measured and computationally derived EXAFS spectra.
- The predicted europium coordination structure in LBCP complexes was supported by the results.
Conclusions:
- The study successfully resolved the structure of europium complexes with LBCPs in solution.
- Combining MD simulations and EXAFS spectroscopy is a powerful tool for studying lanthanide-ligand complex structures.
- The findings advance the understanding of LBCP selectivity and coordination chemistry.
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