June 23, 2003

Lynn induces self-formation of protein nanotubes

By Beverly Clark

Researchers at Emory and Argonne National Laboratory have discovered a new method to manipulate the self-assembly and formation of amyloid fibrils—a major component of brain plaques associated with Alzheimer’s disease—thereby opening new avenues for examination of their formation and for the construction of robust nanotubes that have potential applications in research, industry and medicine.

Certain short amino acid chains (the building blocks of proteins) are capable of self-assembly into the disease-causing amyloid fibrils of Alzheimer’s. David Lynn, Asa Griggs Candler Professor of Chemistry and Biology, and his colleagues have enticed these amyloid peptides to self-assemble into well-defined nanotubes 15 billionths of a meter across.

Such nanotubes can now serve as minute scaffolds to build nanotechnological devices with potential applications in many fields. These findings were published in the May 21 issue of the Journal of the American Chemical Society in their paper “Exploiting Amyloid Fibril Lamination for Nanotube Self-Assembly.”

“We took what we know about amyloid fibril self-assembly and used that information to construct novel, self-assembling nanotubes,” Lynn said. “The creation of these new structures will in turn teach us more about the physical properties of amyloids and the pathways to their formation, which puts us in a better position to understand why they are so damaging and cause disease.”

The discovery underscores the potential of the emerging field of “synthetic biology,” demonstrating the use of self-assembling elements that nature goes to great lengths to avoid, and converting them to new functional materials, Lynn said.

“Nature goes to extreme measures to keep these amyloids from forming, but nature still hasn’t figured out a way on its own to totally control the formation of them,” he continued. “What we have uncovered is a way to control and manipulate the amyloid in a way that nature can’t, so that it acts differently and takes on a new form as a self-assembling nanotube that has many applications for nanotechnology.”

Lynn works in the areas of biomolecular chemistry, molecular evolution and chemical biology. His research in biological chemistry focuses on the spontaneous self-assembly of biological structures, including protein folding, nucleic acid assembly and the organogenesis of multicellular organisms—the basis of the energies that control self-assembly.

Lynn’s research team includes graduate student Kun Lu; Vincent Conticello, professor of biomaterials; and Jaby Jacob and Pappannan Thiyagarajan of the Argonne National Laboratory at the University of Chicago.