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Parallel ?-sheet secondary structure is stabilized and terminated by interstrand disulfide cross-linking.

ABSTRACT: Disulfide bonds between Cys residues in adjacent strands of parallel ?-sheets are rare among proteins, which suggests that parallel ?-sheet structure is not stabilized by such disulfide cross-links. We report experimental results that show, surprisingly, that an interstrand disulfide bond can stabilize parallel ?-sheets formed by an autonomously folding peptide in aqueous solution. NMR analysis reveals that parallel ?-sheet structure is terminated beyond the disulfide bond, which causes deviation from the extended backbone conformation at one of the Cys residues.

SUBMITTER: Almeida AM

PROVIDER: S-EPMC3266109 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Parallel β-sheet secondary structure is stabilized and terminated by interstrand disulfide cross-linking.

Almeida Aaron M AM Li Rebecca R Gellman Samuel H SH

Journal of the American Chemical Society 20111213 1

Disulfide bonds between Cys residues in adjacent strands of parallel β-sheets are rare among proteins, which suggests that parallel β-sheet structure is not stabilized by such disulfide cross-links. We report experimental results that show, surprisingly, that an interstrand disulfide bond can stabilize parallel β-sheets formed by an autonomously folding peptide in aqueous solution. NMR analysis reveals that parallel β-sheet structure is terminated beyond the disulfide bond, which causes deviatio ...[more]

PMID: 22148521

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