A peptide from human semenogelin I self-assembles into a pH-responsive hydrogel.

Area of Science:

• Biomaterials Science
• Protein Self-Assembly
• Biomedical Engineering

Background:

• Human semenogelin I contains peptide sequences with self-assembly properties.
• Self-assembling peptides are promising for developing novel biomaterials.

Purpose of the Study:

• To investigate the self-assembly behavior of the peptide GSFSIQYTYHV derived from human semenogelin I.
• To characterize the resulting hydrogel properties and structure.
• To explore its potential for biomedical applications.

Main Methods:

• Peptide synthesis and characterization.
• Rheological measurements to assess hydrogel elasticity.
• Spectroscopic techniques (CD, fluorescence, FTIR) and cryo-TEM for structural analysis.
• Dynamic light scattering for fibril length determination.
• Thioflavin T fluorescence assay for fibril formation kinetics.

Main Results:

• The peptide GSFSIQYTYHV spontaneously forms a transparent hydrogel in water at neutral pH.
• The hydrogel exhibits a dominant elastic response across a wide frequency range.
• Structural studies indicate the formation of long, micrometer-scale fibrillar aggregates with extended β-sheet conformation.
• Fibril formation follows a nucleated reaction pathway.

Conclusions:

• The peptide GSFSIQYTYHV self-assembles into a physically stable hydrogel with potential for biomaterial development.
• Its low immunogenicity and self-assembling nature make it suitable for biomedical applications such as drug delivery and wound healing.
• This peptide serves as a promising building block for advanced smart biomaterials.