A disulfide polymerized protein crystal

Area of Science:

• Biochemistry
• Structural Biology
• Materials Science

Background:

• The coiled-coil domain of human BAP29 (vDED) is involved in protein-protein interactions.
• Understanding protein self-assembly is crucial for developing novel biomaterials.

Purpose of the Study:

• To investigate the structural properties of the vDED coiled-coil domain.
• To explore the potential for designing self-polymerizing protein crystals.

Main Methods:

• Crystallization of the vDED coiled-coil domain from human BAP29 in dimeric and tetrameric forms.
• Analysis of crystal structures to identify intermolecular interactions.

Main Results:

• The vDED domain crystallized in both dimeric and tetrameric forms.
• A disulfide bond unexpectedly formed between crystal contacts in the dimeric form.
• This disulfide bond resulted in complete cross-linking along the c-axis, demonstrating spontaneous polymerization.

Conclusions:

• It is possible to design protein crystals that exhibit spontaneous polymerization.
• This discovery has implications for the development of self-assembling protein-based materials.