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Solid-State NMR characterization of autofluorescent fibrils formed by the elastin-derived peptide GVGVAGVG.

ABSTRACT: The characterization of the molecular structure and physical properties of self-assembling peptides is an important aspect of optimizing their utility as scaffolds for biomaterials and other applications. Here we report the formation of autofluorescent fibrils by an octapeptide (GVGVAGVG) derived via a single amino acid substitution in one of the hydrophobic repeat elements of human elastin. This is the shortest and most well-defined peptide so far reported to exhibit intrinsic fluorescence in the absence of a discrete fluorophore. Structural characterization by FTIR and solid-state NMR reveals a predominantly ?-sheet conformation for the peptide in the fibrils, which are likely assembled in an amyloid-like cross-? structure. Investigation of dynamics and the effects of hydration on the peptide are consistent with a rigid, water excluded structure, which has implications for the likely mechanism of intrinsic fibril fluorescence.

SUBMITTER: Sharpe S

PROVIDER: S-EPMC3089984 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Solid-State NMR characterization of autofluorescent fibrils formed by the elastin-derived peptide GVGVAGVG.

Sharpe Simon S Simonetti Karen K Yau Jason J Walsh Patrick P

Biomacromolecules 20110401 5

The characterization of the molecular structure and physical properties of self-assembling peptides is an important aspect of optimizing their utility as scaffolds for biomaterials and other applications. Here we report the formation of autofluorescent fibrils by an octapeptide (GVGVAGVG) derived via a single amino acid substitution in one of the hydrophobic repeat elements of human elastin. This is the shortest and most well-defined peptide so far reported to exhibit intrinsic fluorescence in t ...[more]

PMID: 21456595

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