Electrostatic Self-Assembly of Protein Nanoparticles from Intrinsically Disordered Polypeptide and Globular Protein...

Area of Science:

• Biotechnology and Biomaterials Engineering
• Protein Engineering and Therapeutics
• Nanotechnology for Drug Delivery

Background:

• Intracellular delivery of functional proteins is a major challenge for protein therapeutics.
• Existing methods often require harsh conditions or lack efficiency for delivering folded proteins.

Purpose of the Study:

• To present a novel, fully aqueous, genetically encoded platform for assembling protein nanoparticles.
• To enable efficient intracellular delivery of folded, functional proteins using these engineered nanoparticles.

Main Methods:

• Utilized electrostatic coacervation between anionic globular proteins and multi-domain intrinsically disordered proteins (IDPs).
• IDPs comprised a neutral elastin-like polypeptide (ELP) domain and a cationic histone-derived domain (H5).
• Characterized nanoparticle assembly using dynamic light scattering (DLS), fluorescence correlation spectroscopy (FCS), transmission electron microscopy (TEM), and small-angle X-ray scattering (SAXS).

Main Results:

• Successfully formed homogeneous micellar protein nanoparticles with high protein payload retention under mild, aqueous conditions.
• Demonstrated modular control over nanoparticle properties (charge density, ELP length, stoichiometry) enabling tunable size and physicochemical characteristics.
• Achieved well-defined particles with low dispersity and remarkable formulation tolerance.

Conclusions:

• Established a robust and programmable platform for protein-based nanoparticle engineering.
• The system offers a versatile approach for intracellular protein delivery, overcoming critical barriers in protein therapeutics.
• Potential applications in developing advanced protein delivery systems for various therapeutic strategies.