The use of proteins to build artificial supramolecular nanostructures has advanced with the development by a team at the University of Pennsylvania of a computational method to design peptides that will self-organize into specific supramolecular structures on a given surface. Specifically, they designed peptides that assemble on the surface of carbon nanotubes in much the same way that viral coat proteins assemble on the viral nucleic acid. PhysOrg.com points to this Penn news release “Penn Researchers Help Nanoscale Engineers Choose Self-Assembling Proteins“:
Engineering structures on the smallest possible scales — using molecules and individual atoms as building blocks — is both physically and conceptually challenging. An interdisciplinary team of researchers at the University of Pennsylvania has now developed a method of computationally selecting the best of these blocks, drawing inspiration from the similar behavior of proteins in making biological structures.
The team was led by postdoctoral fellow Gevorg Grigoryan and professor William DeGrado of the Department of Biochemistry and Biophysics in Penn’s Perelman School of Medicine, as well as graduate student Yong Ho Kim of the Department of Chemistry in Penn’s School of Arts and Sciences. Their colleagues included members of the Department of Physics and Astronomy in SAS.
Their research was published in the journal Science [abstract].
The team set out to design proteins that could wrap around single-walled carbon nanotubes. …
“We wanted to achieve a specific geometric pattern of the atoms that these proteins are composed of on the surface of the nanotube,” Grigoryan said. “If you know the underlying atomic lattice, it means that you know how to further build around it, how to attach things to it. It’s like scaffolding for future building.” …
The researchers designed an algorithm that sifts through hundreds of thousands of atomically detailed actual and potential protein structures and compares them with the structural parameters of the desired scaffolding. The algorithm was used to design a protein “that would not only stably wrap around a nanotube in a helix but also provide a regular pattern on its exterior to which gold particles could be attached.”
“You could use this to build a gold nanowire, for instance, or modulate the optical properties of the underlying tube in desired ways” Grigoryan said.
Next steps will include applying this algorithm for designing proteins that can attach to graphene, which is essentially an unrolled nanotube. Being able to make scaffolds out of customizable array of proteins in a variety of shapes could lead to advances in everything from miniaturization of circuitry to drug delivery.
Since this assembly process mimics the self-assembly process of viral coat proteins, it will be interesting to compare progress using this approach with the progress of other research groups engineering virus proteins for nanotechnology purposes.