Computational Design of Virus-Like Protein Assemblies on Carbon Nanotube Surfaces

Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA.
Science (Impact Factor: 33.61). 05/2011; 332(6033):1071-6. DOI: 10.1126/science.1198841
Source: PubMed


There is a general need for the engineering of protein-like molecules that organize into geometrically specific superstructures on molecular surfaces, directing further functionalization to create richly textured, multilayered assemblies. Here we describe a computational approach whereby the surface properties and symmetry of a targeted surface define the sequence and superstructure of surface-organizing peptides. Computational design proceeds in a series of steps that encode both surface recognition and favorable intersubunit packing interactions. This procedure is exemplified in the design of peptides that assemble into a tubular structure surrounding single-walled carbon nanotubes (SWNTs). The geometrically defined, virus-like coating created by these peptides converts the smooth surfaces of SWNTs into highly textured assemblies with long-scale order, capable of directing the assembly of gold nanoparticles into helical arrays along the SWNT axis.

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    • "We repeat this process of iteratively searching for pairs of residues at a time and incorporating clusters from the search results until we assemble a native-like fragment of a sheet where almost every residue originates from a unique protein structure (two disconnected threonines were inadvertently drawn from the same structure). This then provides α-carbon coordinates that we feed into the backbone search engine MaDCaT [10], which finds suitable scaffolds to incorporate this fragment. One MaDCaT search result greatly resembles the β sheet built using Suns (Figure 4C). "
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