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Impact of Strand Number on Parallel ?-Sheet Stability.

ABSTRACT: We have examined whether parallel ?-sheet secondary structure becomes more stable as the number of ?-strands increases, via comparisons among peptides designed to adopt two- or three-stranded parallel ?-sheet conformations in aqueous solution. Our three-strand design is the first experimental model of a triple-stranded parallel ?-sheet. Analysis of the designed peptides by nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopy supports the hypothesis that increasing the number of ?-strands, from two to three, increases the stability of the parallel ?-sheet. We present the first experimental evidence for cooperativity in the folding of a triple-stranded parallel ?-sheet, and we show how minimal model systems may enable experimental documentation of characteristic properties, such as CD spectra, of parallel ?-sheets.

SUBMITTER: Kung VM

PROVIDER: S-EPMC4715541 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Impact of Strand Number on Parallel β-Sheet Stability.

Kung Vanessa M VM Cornilescu Gabriel G Gellman Samuel H SH

Angewandte Chemie (International ed. in English) 20151012 48

We have examined whether parallel β-sheet secondary structure becomes more stable as the number of β-strands increases, via comparisons among peptides designed to adopt two- or three-stranded parallel β-sheet conformations in aqueous solution. Our three-strand design is the first experimental model of a triple-stranded parallel β-sheet. Analysis of the designed peptides by nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopy supports the hypothesis that increasing the number ...[more]

PMID: 26457984

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