Displaying a Protein Cage on a Protein Crystal by In-Cell Crystal Engineering

Area of Science:

• Bionanotechnology
• Biomaterials Science
• Protein Engineering

Background:

• Solid biomaterials are advancing rapidly for bionanotechnology.
• Immobilizing proteins, like enzymes, within protein crystals creates functionalized materials and solid catalysts.
• Efficient methods for encapsulating protein assemblies are lacking.

Purpose of the Study:

• To present a novel method for displaying protein cages onto a crystalline protein scaffold.
• To engineer in-cell protein crystals for enhanced biomaterial development.

Main Methods:

• Coexpression of polyhedrin monomer (PhM) and H1-ferritin (H1-Fr) monomer in Escherichia coli.
• Utilizing in-cell protein crystal engineering to create a polyhedra crystal (PhC) scaffold displaying a ferritin cage.
• Employing an H1-tag derived from the H1-helix of PhM.

Main Results:

• Successfully produced a polyhedra crystal (PhC) scaffold displaying a ferritin cage.
• Demonstrated a novel approach for protein assembly immobilization within in-cell protein crystals.
• Established a viable method for creating functionalized protein crystals.

Conclusions:

• The developed technique offers a unique strategy for immobilizing protein assemblies onto in-cell protein crystals.
• This method is expected to significantly contribute to advancements in bionanotechnology.
• The engineered protein crystals provide a new platform for developing solid catalysts and functionalized materials.