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Updated: Jan 11, 2026
08:53
Biochemical and Structural Characterization of the Carbohydrate Transport Substrate-binding-protein SP0092
Published on: October 2, 2017
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Structural insights into substrate binding of SLC19A3: Comparing inward-open and outward-open conformations
Enhao Zhang1, Xiaole Xu1, Jinxin Liu1
1School of Physics and Electronics, Shandong Normal University, Jinan, 250014, China.
International Journal of Biological Macromolecules
|November 8, 2025
Summary
The SLC19A3 protein
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- SLC19A3 facilitates thiamine uptake in vital organs.
- Understanding SLC19A3's substrate binding mechanism is crucial.
- Distinct conformational states of SLC19A3 are known, but their functional implications are unclear.
Purpose of the Study:
- To investigate the mechanistic basis of substrate recognition and binding in SLC19A3.
- To explore the impact of mutations on SLC19A3's conformational states.
- To compare ligand interactions across different SLC19A3 conformations.
Main Methods:
- Molecular dynamics simulations were utilized.
- Interactions between SLC19A3 and various substrates were analyzed.
- Comparative analysis of ligand binding in distinct conformational states was performed.
Main Results:
- Mutations were found to affect distinct conformational states of SLC19A3.
- The outward-open conformation showed altered binding affinities: weaker for thiamine, stronger for amprolium and fedratinib.
- The inward-open conformation exhibited conserved binding modes for all tested ligands.
Conclusions:
- SLC19A3's molecular mechanisms, particularly ligand interactions in different conformations, are elucidated.
- Understanding these mechanisms is key to explaining mutation-related diseases.
- This research provides a foundation for developing new therapeutic strategies targeting SLC19A3.
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