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Bulky Dehydroamino Acids Enhance Proteolytic Stability and Folding in ?-Hairpin Peptides.

ABSTRACT: The bulky dehydroamino acids dehydrovaline (?Val) and dehydroethylnorvaline (?Env) can be inserted into the turn regions of ?-hairpin peptides without altering their secondary structures. These residues increase proteolytic stability, with ?Val at the (i + 1) position having the most substantial impact. Additionally, a bulky dehydroamino acid can be paired with a d-amino acid (i.e., d-Pro) to synergistically enhance resistance to proteolysis. A link between proteolytic stability and peptide structure is established by the finding that a stabilized ?Val-containing ?-hairpin is more highly folded than its Asn-containing congener.

SUBMITTER: Jalan A

PROVIDER: S-EPMC6085080 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Bulky Dehydroamino Acids Enhance Proteolytic Stability and Folding in β-Hairpin Peptides.

Jalan Ankur A Kastner David W DW Webber Kei G I KGI Smith Mason S MS Price Joshua L JL Castle Steven L SL

Organic letters 20170914 19

The bulky dehydroamino acids dehydrovaline (ΔVal) and dehydroethylnorvaline (ΔEnv) can be inserted into the turn regions of β-hairpin peptides without altering their secondary structures. These residues increase proteolytic stability, with ΔVal at the (i + 1) position having the most substantial impact. Additionally, a bulky dehydroamino acid can be paired with a d-amino acid (i.e., d-Pro) to synergistically enhance resistance to proteolysis. A link between proteolytic stability and peptide stru ...[more]

PMID: 28910115

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