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Coassembly of enantiomeric amphipathic peptides into amyloid-inspired rippled ?-sheet fibrils.

ABSTRACT: Amphipathic peptides composed of alternating hydrophobic and hydrophilic amino acids self-assemble into amyloid-inspired, ?-sheet nanoribbon fibrils. Herein, we report a new fibril type that is formed from equimolar mixtures of enantiomeric amphipathic peptides (L- and D-(FKFE)(2)). Spectroscopic analysis indicates that these peptides do not self-sort and assemble into enantiomeric fibrils composed of all-l and all-d peptides, but rather coassemble into fibrils that contain alternating L- and D-peptides in a "rippled ?-sheet" orientation. Isothermal titration calorimetry indicates an enthalpic advantage for rippled ?-sheet coassembly compared to self-sorted ?-sheet assembly of enantiomeric peptides.

SUBMITTER: Swanekamp RJ

PROVIDER: S-EPMC7316157 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Coassembly of enantiomeric amphipathic peptides into amyloid-inspired rippled β-sheet fibrils.

Swanekamp Ria J RJ DiMaio John T M JT Bowerman Charles J CJ Nilsson Bradley L BL

Journal of the American Chemical Society 20120316 12

Amphipathic peptides composed of alternating hydrophobic and hydrophilic amino acids self-assemble into amyloid-inspired, β-sheet nanoribbon fibrils. Herein, we report a new fibril type that is formed from equimolar mixtures of enantiomeric amphipathic peptides (L- and D-(FKFE)(2)). Spectroscopic analysis indicates that these peptides do not self-sort and assemble into enantiomeric fibrils composed of all-l and all-d peptides, but rather coassemble into fibrils that contain alternating L- and D- ...[more]

PMID: 22420540

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