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Updated: Aug 15, 2026
07:51
Pull-down of Calmodulin-binding Proteins
Published on: January 23, 2012
Amplification of bifunctional ligands for calmodulin from a dynamic combinatorial library
Lilia Milanesi1, Christopher A Hunter, Svetlana E Sedelnikova
1Centre for Chemical Biology, Krebs Institute for Biomolecular Science, Department of Chemistry, University of Sheffield, Sheffield S3 7HF, UK.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 22, 2005
Summary
Dynamic combinatorial chemistry (DCC) was used to create high-affinity bifunctional ligands. Linking low-affinity thiols into disulfide ligands significantly amplified binding affinity in the presence of calmodulin.
Area of Science:
- Biochemistry
- Chemical Biology
- Molecular Recognition
Background:
- High-affinity ligands are crucial for biological receptor targeting.
- Linking low-affinity ligands is a known strategy to enhance binding.
- Dynamic combinatorial chemistry (DCC) offers a method for ligand discovery.
Purpose of the Study:
- To utilize DCC to select bifunctional protein ligands with enhanced affinity.
- To investigate the role of protein structure, specifically calmodulin, in ligand selection.
- To compare the binding affinity of bifunctional ligands to their monofunctional counterparts.
Main Methods:
- Employing dynamic combinatorial chemistry (DCC) for ligand library generation.
- Utilizing thiol-to-disulfide linkages to create bifunctional ligands.
- Assessing ligand binding affinity in the presence of calmodulin.
Main Results:
- A small dynamic library of bifunctional ligands was generated using thiol-disulfide chemistry.
- The presence of calmodulin significantly amplified the binding affinity of specific bifunctional ligands.
- The most amplified bifunctional ligand exhibited a binding constant nearly two orders of magnitude higher than its monofunctional thiol precursor.
Conclusions:
- DCC is effective in selecting high-affinity bifunctional ligands.
- Protein structure, like calmodulin's mobile domains, can direct the selection of potent ligands.
- Bifunctional ligands generated through DCC show significantly improved binding characteristics compared to monofunctional ones.
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