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Bio-layer Interferometry for Measuring Kinetics of Protein-protein Interactions and Allosteric Ligand Effects
Published on: February 18, 2014
Siderocalin Q83 exhibits differential slow dynamics upon ligand binding
Nicolas Coudevylle1, Leonhard Geist, Matthias Hoetzinger
1Department of Computational and Structural Biology, Max F. Perutz Laboratories, Campus Vienna Biocenter 5, 1030 Vienna, Austria. Nicolas.coudevylle@univie.ac.at
Journal of Biomolecular NMR
|September 28, 2011
Summary
Siderocalin Q83 protein dynamics change upon ligand binding. Binding one molecule, like enterobactin or arachidonic acid, alters the protein
Area of Science:
- Biochemistry
- Structural Biology
- Protein Dynamics
Background:
- Siderocalin Q83 is a soluble protein capable of binding two distinct ligands: enterobactin and arachidonic acid.
- Simultaneous binding occurs at two separate sites within the protein structure.
Purpose of the Study:
- To investigate the dynamic behavior of Siderocalin Q83 in its free and ligand-bound states.
- To elucidate the relationship between ligand binding and protein conformational changes.
Main Methods:
- Utilized techniques to study protein dynamics across micro- to millisecond timescales.
- Analyzed changes in protein motion upon binding of arachidonic acid and enterobactin.
Main Results:
- Free Siderocalin Q83 exhibits significant micro- to millisecond dynamics.
- Binding of arachidonic acid quenches motions at its binding site, increasing dynamics at the enterobactin site.
- Enterobactin binding reciprocally quenches its site's dynamics and enhances slow dynamics at the arachidonic acid site.
Conclusions:
- Ligand binding to Siderocalin Q83 induces allosteric regulation, enhancing affinity for the other ligand.
- Protein dynamics are crucial for function, supporting the view of proteins as dynamic ensembles.
- These findings advance understanding of allosteric mechanisms and protein flexibility.
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