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Crystal structure of an amphiphilic foldamer reveals a 48-mer assembly comprising a hollow truncated octahedron.

ABSTRACT: Foldamers provide an attractive medium to test the mechanisms by which biological macromolecules fold into complex three-dimensional structures, and ultimately to design novel protein-like architectures with properties unprecedented in nature. Here, we describe a large cage-like structure formed from an amphiphilic arylamide foldamer crystallized from aqueous solution. Forty-eight copies of the foldamer assemble into a 5-nm cage-like structure, an omnitruncated octahedron filled with well-ordered ice-like water molecules. The assembly is stabilized by a mix of arylamide stacking interaction, hydrogen bonding and hydrophobic forces. The omnitruncated octahedra tessellate to form a cubic crystal. These findings may provide an important step towards the design of nanostructured particles resembling spherical viruses.

SUBMITTER: Pavone V

PROVIDER: S-EPMC4013780 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Crystal structure of an amphiphilic foldamer reveals a 48-mer assembly comprising a hollow truncated octahedron.

Pavone Vincenzo V Zhang Shao-Qing SQ Merlino Antonello A Lombardi Angela A Wu Yibing Y DeGrado William F WF

Nature communications 20140407

Foldamers provide an attractive medium to test the mechanisms by which biological macromolecules fold into complex three-dimensional structures, and ultimately to design novel protein-like architectures with properties unprecedented in nature. Here, we describe a large cage-like structure formed from an amphiphilic arylamide foldamer crystallized from aqueous solution. Forty-eight copies of the foldamer assemble into a 5-nm cage-like structure, an omnitruncated octahedron filled with well-ordere ...[more]

PMID: 24705140

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