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Updated: May 7, 2026
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Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
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Charge regulation in peptide self-assembly and hydrogelation
Luigi Gentile1, Birgitta Frohm2, Anders Malmendal3
1Department of Chemistry, University of Bari Aldo Moro, Via Orabona 4, 70126 Bari, Italy; Center of Colloid and Surface Science (CSGI), Bari Unit, Via Orabona 4, 70126 Bari, Italy.
Journal of Colloid and Interface Science
|August 7, 2025
Summary
The peptide Ac-KGSFSIQYTYHVD-CONH₂ (KD) forms pH-responsive hydrogels by self-assembling into beta-sheet fibrils. Its mechanical properties are tunable with pH, showing potential for biomaterial applications.
Area of Science:
- Biomaterials Science
- Supramolecular Chemistry
- Biophysics
Background:
- Peptide self-assembly is a key mechanism for creating advanced biomaterials.
- Understanding the pH-dependent structural transitions of peptides is crucial for controlling hydrogel properties.
- Human semenogelin I-derived peptides offer potential for novel hydrogel development.
Purpose of the Study:
- To investigate the pH-dependent self-assembly mechanism of the peptide Ac-KGSFSIQYTYHVD-CONH₂ (KD).
- To elucidate the structural evolution and mechanical property modulation of KD-based hydrogels.
- To explore the potential of KD hydrogels for therapeutic applications.
Main Methods:
- Time-resolved nuclear magnetic resonance (NMR) spectroscopy to monitor structural changes.
- Cryo-transmission electron microscopy (cryo-TEM) for visualizing nanostructures.
- Rheological studies to quantify mechanical properties under varying pH.
- pH measurements to track peptide interactions during gelation.
Main Results:
- KD self-assembles into beta-sheet fibrils, forming a hydrogel network.
- Two distinct nanostructures (fibrils and curly nanostructures) were observed via cryo-TEM.
- A significant increase in elastic modulus was correlated with pH shifts.
- The peptide exhibited rapid hydrogel formation under buffered conditions.
Conclusions:
- The pH-responsive hydrogel formation of KD is primarily driven by histidine protonation.
- KD hydrogels demonstrate dynamic tunability of mechanical properties.
- These findings provide mechanistic insights for designing peptide-based biomaterials for therapeutic use.
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