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Updated: Jul 9, 2026
14:44
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Protein-Enforced Ligand Environments Reshape Classical Coordination Preferences in Copper Polypyridyl Complexes
Inseo Choi1, Jaehee Lee1, Kyohyun Hwang1
1Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea.
Journal of the American Chemical Society
|July 8, 2026
Summary
Researchers engineered protein scaffolds to control copper
Area of Science:
- Bioinorganic Chemistry
- Protein Engineering
- Coordination Chemistry
Background:
- Copper coordination chemistry exhibits Jahn-Teller distortion in Cu(II) and limited high-coordinate Cu(I) species.
- Intrinsic electronic and structural preferences of copper limit coordination environments.
Purpose of the Study:
- To demonstrate protein scaffolds as mechanically active ligands overriding intrinsic copper preferences.
- To create novel mononuclear copper sites within engineered protein environments.
Main Methods:
- Designed four protein scaffolds with preorganized bipyridine-alanine noncanonical amino acids.
- Generated mononuclear copper sites in both cupric (Cu(II)) and cuprous (Cu(I)) states within protein scaffolds.
Main Results:
- Achieved distinct charge-transfer features and enhanced structural symmetry.
- Significantly reduced Jahn-Teller distortion and observed unprecedented octahedral Cu(I) geometry.
- Reported cathodic shifts in redox potentials and rapid self-exchange rates, indicating entatic-state behavior.
Conclusions:
- Protein scaffolds serve as effective multidentate ligands for nonclassical coordination environments.
- Protein-imposed strains expand the chemical space and reactivity of metalloproteins.
- This strategy offers a general approach to designing novel metalloprotein active sites.
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