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Updated: Feb 10, 2026
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Paramagnetic Relaxation Enhancement for Detecting and Characterizing Self-Associations of Intrinsically Disordered Proteins
Published on: September 23, 2021
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Facilitated Protein Association via Engineered Target Search Pathways Visualized by Paramagnetic NMR Spectroscopy
So Young An1, Eun-Hee Kim2, Jeong-Yong Suh3
1Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
Structure (London, England : 1993)
|May 22, 2018
Summary
Researchers engineered protein interactions by modifying target search pathways. Mutations created new on-pathway encounter complexes, significantly increasing binding affinity and demonstrating a new method for protein engineering.
Area of Science:
- Biochemistry
- Structural Biology
- Protein Engineering
Background:
- Proteins form functional complexes through progressive evolution of nonspecific encounters.
- Protein-protein interactions involve complex target search processes with multiple routes.
Purpose of the Study:
- To visualize encounter complexes between histidine-containing phosphocarrier protein and enzyme I N-terminal domain.
- To demonstrate that protein association can be enhanced by engineering on-pathways.
Main Methods:
- Utilized NMR paramagnetic relaxation enhancement to visualize encounter complexes.
- Introduced mutations in surface charges away from the binding interface to engineer on-pathways.
Main Results:
- Engineered on-pathways created new encounter complexes, increasing binding affinity by an order of magnitude.
- The structure of engineered complexes revealed extended target search processes.
- Countering mutations that blocked on-pathways reverted the enhanced binding affinity.
Conclusions:
- Protein interactions can be engineered by rewiring the target search process.
- Modifying non-interface surface charges can create novel on-pathway complexes.
- This approach offers a powerful strategy for protein interaction engineering.
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