A Method to Design Self-Assembling Proteins

Case 1999-246

BACKGROUND

Understanding the roles that molecular structure and self-assembly play in determining molecular architecture helps provide researchers with the possibility of designing unique materials using nanotechnology. Molecular self-assembly entails designing various molecules so shape-complementarity causes them to aggregate into specified structures. A major goal in nanotechnology is developing a single method for fabricating materials having different architectures and symmetries.

INNOVATION

UC researchers have accomplished this goal by developing a method to design proteins which will assemble into large symmetric materials from naturally symmetric oligomeric proteins. Component proteins are then combined in a well-defined fashion according to specified geometrical rules. The researchers have been able to construct well-defined protein-based shells and cages on the 10 to 20 nanometer length scale.

APPLICATIONS

The methodology of designing self-assembling proteins can useful in the fields of nanotechnology and materials science. One major area for use is in drug delivery. In addition, the particles can be used to display multiple copies of antigens on their surface. In developing vaccines, this multivalent display tends to give extra strong immune responses.

ADVANTAGES

• Internal structures of individual protein domains are not altered and it is sufficient to fuse naturally occurring proteins without making internal modifications.
• There is significant combinatorial power from connecting multiple protein components.
• Individual amino acids or additional protein domains can be incorporated easily in order to carry enzymatic activity, ligands for specific receptors, sites for specific chemical modifications, and antigenic epitopes.
• The chemical diversity of the proteins allows the incorporation of proteins with metal or ligand-sensitive conformations to form materials that will assemble and disassemble in response to a signal.