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A Tripeptide-Stabilized Nanoemulsion of Oleic Acid
Published on: February 27, 2019
Rational design of a reversible pH-responsive switch for peptide self-assembly
Yuri Zimenkov1, Steven N Dublin, Rong Ni
1Department of Chemistry and The Integrated Microscopy and Microanalytical Facility, Emory University, 1515 Dickey Drive, Atlanta, GA 30322, USA.
Journal of the American Chemical Society
|May 25, 2006
Summary
Peptide TZ1H self-assembles into helical fibers reversibly, controlled by pH. This pH-dependent assembly is linked to histidine protonation, enabling tunable material properties.
Area of Science:
- Biomaterials science
- Protein engineering
- Supramolecular chemistry
Background:
- Coiled-coil peptides are fundamental protein structures.
- Controlling peptide self-assembly is key for biomaterial design.
- pH-responsive materials offer tunable properties.
Purpose of the Study:
- To engineer a pH-responsive peptide that self-assembles into helical fibers.
- To investigate the mechanism of pH-dependent self-assembly.
- To correlate conformational changes with protonation states.
Main Methods:
- Peptide synthesis and characterization (TZ1H).
- Circular dichroism spectroscopy for conformational analysis.
- Transmission electron microscopy for fiber imaging.
- Microrheology for mechanical property assessment.
Main Results:
- Peptide TZ1H self-assembles into long helical fibers reversibly.
- Assembly is pH-dependent, occurring within a narrow pH range.
- Histidine substitution at d-positions couples assembly to imidazole protonation.
- A coil-helix conformational transition accompanies self-assembly.
Conclusions:
- Engineered histidine residues enable precise pH control over peptide self-assembly.
- The study demonstrates a mechanism for creating tunable, pH-responsive biomaterials.
- TZ1H peptide offers a platform for developing advanced functional materials.
