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Aromatic-Aromatic Interactions Enable ?-Helix to ?-Sheet Transition of Peptides to Form Supramolecular Hydrogels.

ABSTRACT: Isolated short peptides usually are unable to maintain their original secondary structures due to the lack of the restriction from proteins. Here we show that two complementary pentapeptides from a ?-sheet motif of a protein, being connected to an aromatic motif (i.e., pyrene) at their C-terminal, self-assemble to form ?-sheet like structures upon mixing. Besides enabling the self-assembly to result in supramolecular hydrogels upon mixing, aromatic-aromatic interactions promote the pentapeptides transform from ?-helix to ?-sheet conformation. As the first example of using aromatic-aromatic interactions to mimic the conformational restriction in a protein, this work illustrates a bioinspired way to generate peptide nanofibers with predefined secondary structures of the peptides by a rational design using protein structures as the blueprint.

SUBMITTER: Li J

PROVIDER: S-EPMC5477776 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Aromatic-Aromatic Interactions Enable α-Helix to β-Sheet Transition of Peptides to Form Supramolecular Hydrogels.

Li Jie J Du Xuewen X Hashim Saqib S Shy Adrianna A Xu Bing B

Journal of the American Chemical Society 20161222 1

Isolated short peptides usually are unable to maintain their original secondary structures due to the lack of the restriction from proteins. Here we show that two complementary pentapeptides from a β-sheet motif of a protein, being connected to an aromatic motif (i.e., pyrene) at their C-terminal, self-assemble to form β-sheet like structures upon mixing. Besides enabling the self-assembly to result in supramolecular hydrogels upon mixing, aromatic-aromatic interactions promote the pentapeptides ...[more]

PMID: 27997165

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