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Updated: Jul 25, 2025
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Systematic elucidation of the second coordination sphere effect on the structure and properties of a blue copper
Takahide Yamaguchi1, Attila Taborosi2, Chihiro Sakai3
1Institute of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, Mito, Ibaraki 310-8512, Japan; Frontier Research Center for Applied Atomic Sciences, Ibaraki University, 162-1, Shirakata, Tokai, Ibaraki 319-1106, Japan.
Abstract:
The rational structural and computational studies of a blue copper protein, pseudoazurin (PAz), and its Met16X (X = Phe, Leu, Val, Ile) variants gave clear functional meanings of the noncovalent interaction (NCI) through the second coordination sphere. The high-resolution X-ray crystal structures of Met16X PAz demonstrated that the active site geometry is significantly affected by the substitution of Met16, which is located within the NCI distance from the His81 imidazole ring at the copper active site. The computational chemistry calculations based on the crystal structure analyses confirmed that the NCI of S-π/CH-π (wild-type), π-π (Met16Phe), double CH-π (Met16Leu), and single CH-π (Met16Val and Met16Ile). The estimated interaction energies for the NCI demonstrated that the fine-tuning of the protein stability and Cu site properties form the second coordination sphere of PAz.
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