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Updated: May 11, 2026
07:51
Pull-down of Calmodulin-binding Proteins
Published on: January 23, 2012
Calcium binding peptide motifs from calmodulin confer divalent ion selectivity to elastin-like polypeptides
Wafa Hassouneh1, Michelle L Nunalee, M Coleman Shelton
1Department of Biomedical Engineering, Campus Box 90281, Duke University, Durham, North Carolina 27708, United States.
Biomacromolecules
|May 28, 2013
Summary
Researchers developed calcium-sensitive elastin-like polypeptides (CELPs) that self-assemble into nanoparticles. These novel peptide polymers respond to calcium, forming micelles at specific temperatures and concentrations.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Elastin-like polypeptides (ELPs) are stimuli-responsive biopolymers with tunable properties.
- Calmodulin contains a calcium-binding peptide sequence that can be integrated into other polymers.
- Developing responsive materials for controlled self-assembly is a key area in nanotechnology.
Purpose of the Study:
- To synthesize and characterize calcium-sensitive elastin-like polypeptides (CELPs).
- To investigate the calcium responsiveness and selectivity of CELPs.
- To utilize CELPs for the creation of calcium-sensitive nanoparticles.
Main Methods:
- Periodic incorporation of a calmodulin-derived calcium-binding sequence into an ELP backbone.
- Synthesis of diblock copolymers by fusing a hydrophilic ELP with a CELP block.
- Characterization of self-assembly behavior of diblock polypeptides in response to calcium ions.
Main Results:
- CELPs demonstrated sensitivity to calcium, though with less selectivity over magnesium compared to calmodulin.
- Diblock polypeptides comprising hydrophilic ELP and CELP blocks were synthesized.
- Calcium addition (50-500 mM) induced amphiphilicity and self-assembly into spherical micelles (∼50 nm hydrodynamic radius) at 33-46 °C.
Conclusions:
- Novel calcium-sensitive elastin-like polypeptides (CELPs) were successfully synthesized.
- These CELPs can serve as building blocks for stimuli-responsive nanoparticles.
- The self-assembly into micelles is controllable by calcium concentration and temperature, offering potential applications in drug delivery and biomaterials.
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