NMR-structural investigations of a β3-dodecapeptide with proteinogenic side chains in methanol and in aqueous solutions

Touraj Etezady-Esfarjani, Christian Hilty, Kurt Wüthrich, Magnus Rueping, Jürg Schreiber, Dieter Seebach

Research output: Contribution to journalArticlepeer-review

44 Scopus citations

Abstract

The structural properties of an all-β3-dodecapeptide with the sequence H-β-HLys(Nε-CO(CH2)3-S-Acm)- β-HPhe-β-HTyr-β-HLeu-β-HLys-β-HSer-β- HLys-β-HPhe-β-HSer-β-HVal-β-HLys-β-HAla-0H (1) have been studied by two-dimensional homonuclear 1H-NMR and by CD spectroscopy. In MeOH solution, high resolution NMR spectroscopy showed that the β-dodecapeptide forms an (M)-314-helix, and the CD spectrum corresponds to the pattern expected for an (M)-314-helical secondary structure. In aqueous solution, however, the peptide adopts a predominantly extended conformation without regular secondary-structure elements, which is in agreement with the absence of the characteristic trough near 215 nm in the CD spectrum. The NMR and CD measurements with solutions of 1 in MeOH containing 3M urea further indicated that the peptide retains the regular secondary structural elements under these conditions, whereas, after addition of 40% (v/v) H2O to the MeOH solution, the large 1H-chemical-shift dispersion indicative of a defined spatial peptide fold was lost. The β3-dodecapeptide is - so far - the longest β-peptide shown to adopt a regular (M)-314-helix conformation in an organic solvent. The observation that the structure of this long β3-peptide is not maintained in aqueous solution indicates that the (M)-314-fold is primarily stabilized by short-range interactions.

Original languageEnglish (US)
Pages (from-to)1197-1209
Number of pages13
JournalHelvetica Chimica Acta
Volume85
Issue number5
DOIs
StatePublished - Jun 18 2002

ASJC Scopus subject areas

  • Catalysis
  • Biochemistry
  • Drug Discovery
  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Inorganic Chemistry

Fingerprint

Dive into the research topics of 'NMR-structural investigations of a β<sup>3</sup>-dodecapeptide with proteinogenic side chains in methanol and in aqueous solutions'. Together they form a unique fingerprint.

Cite this