Designed Artificial Protein Heterodimers With Coupled Functions Constructed Using Bio-Orthogonal Chemistry

Area of Science:

• Biochemistry
• Synthetic Biology
• Protein Engineering

Background:

• Protein complexes are fundamental to biological processes, often displaying unique functions not found in monomers.
• Linking functionally and structurally distinct proteins can yield novel properties for synthetic biology and nanoscience.

Purpose of the Study:

• To design and construct a heterodimeric protein complex by covalently linking cytochrome b562 and green fluorescent protein (GFP).
• To explore the creation of new functional properties through the combination of disparate protein units.

Main Methods:

• Computational docking was employed to identify compatible interfaces for protein linkage.
• Genetic code expansion was used to introduce azide and alkyne functionalities for triazole linkage formation.
• Spectroscopic analysis was performed to characterize the resulting heterodimer.

Main Results:

• A stable heterodimer of cytochrome b562 and GFP was successfully synthesized via a triazole linkage.
• Both the haem-binding ability of cytochrome b562 and the fluorescence of GFP were preserved in the complex.
• Functional communication between the linked proteins was observed, influenced by the specific linkage site.

Conclusions:

• It is feasible to design and create heterodimeric proteins by coupling structurally and functionally distinct protein units.
• Engineered protein complexes can exhibit novel emergent properties, expanding possibilities in synthetic biology.
• The linkage site plays a crucial role in mediating functional communication within the heterodimer.