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Updated: Jan 27, 2026
14:44
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
10.1K
How Outer Coordination Sphere Modifications Can Impact Metal Structures in Proteins: A Crystallographic Evaluation
Leela Ruckthong1,2, Jeanne A Stuckey3,4, Vincent L Pecoraro1
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109, USA.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|March 13, 2019
Summary
Controlling metal coordination in de novo metalloproteins is achieved by modifying amino acid residues. These changes fine-tune metal properties by altering the active site
Area of Science:
- Protein Engineering
- Biochemistry
- Structural Biology
Background:
- De novo metalloprotein design aims to control metal properties via outer coordination spheres.
- Three-stranded coiled coils (TRI and CoilSer peptides) serve as model systems.
- Cysteine substitution creates thiophilic sites, influencing metal coordination geometry.
Purpose of the Study:
- To investigate how modifications in metalloprotein active sites influence metal coordination number and geometry.
- To elucidate the structural basis for observed variations in cadmium coordination using X-ray crystallography.
Main Methods:
- High-resolution X-ray crystallography of apo- and mercurated TRI/CoilSer peptides.
- Comparison of structural data to understand residue-specific effects on metal binding.
- Site-directed mutagenesis using coded and non-coded amino acids.
Main Results:
- Alanine substitution for leucine creates a cavity, facilitating water coordination (CdII S3(OH2)x).
- Proline substitution for cysteine restricts rotation, leading to water displacement (CdII S3).
- D-leucine substitutions modulate space, influencing water accommodation and coordination (CdII S3, CdII S3(OH2), CdII S3(OH2)2).
Conclusions:
- Specific amino acid substitutions precisely control metal coordination number and geometry in de novo metalloproteins.
- Understanding these structure-function relationships enables rational design of metalloproteins with tailored metal properties.
- Coded and non-coded amino acids are valuable tools for fine-tuning metalloprotein active sites.
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