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Updated: Jun 5, 2025
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Electronic structures of blue copper centers of amicyanin and azurin in the solution state
Yudai Izumi1, Ralph Ugalino1,2, Jun Miyawaki2
1Institute for Quantum Life Science, National Institutes for Quantum Science and Technology (QST), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555, Japan. fujii.kentaro@qst.go.jp.
Abstract:
X-ray absorption near edge structure (XANES) spectra of blue copper proteins, amicyanin and azurin, in the solution state were measured in the copper L3-edge energy region. The absorption peak energies were quite similar for both proteins, while the main edge region for azurin was broader than that for amicyanin, owing to more pronounced shoulder spectral features in the former. Ab initio calculations at the whole protein level qualitatively reproduced the experimental spectra well. The relative X-ray absorption intensities suggest that the degree of covalency of the copper-ligand bond at the active site was weaker for amicyanin than that for azurin.
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