Cytochrome display on amyloid fibrils

Area of Science:

• Biotechnology
• Materials Science
• Protein Engineering

Background:

• Protein amyloid fibrils offer a scaffold for functionalization.
• Appending functional domains to amyloidogenic proteins enables tailored fibril properties.

Purpose of the Study:

• To engineer protein amyloid fibrils displaying biologically functional porphyrins.
• To create a fusion protein of cytochrome b562 and an SH3 dimer for amyloid fibril formation and metalloporphyrin binding.

Main Methods:

• Genetic fusion of cytochrome b562 and SH3 dimer sequences.
• Amyloid fibril self-assembly under defined conditions.
• Spectroscopic analysis (UV-vis, NMR) to confirm metalloporphyrin binding and holo-cytochrome formation.

Main Results:

• The fusion protein successfully formed amyloid fibrils.
• Bound metalloporphyrins at approximately 50% of binding sites.
• Resulting holo-cytochrome domains were spectroscopically identical to wild-type cytochrome.
• High concentration of metalloporphyrins (approx. 20 mM) achieved on saturated fibrils.

Conclusions:

• Engineered protein amyloid fibrils can display functional metalloporphyrins.
• This system demonstrates potential for advanced nanotechnology applications.
• The method provides a robust way to create highly concentrated functionalized biomaterials.