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Updated: Jan 27, 2026
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Oligopeptide Competition Assay for Phosphorylation Site Determination
Published on: May 18, 2017
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Heterochiral Ala/(αMe)Aze sequential oligopeptides: Synthesis and conformational study
Bruno Drouillat1, Cristina Peggion2, Barbara Biondi3
1Institut Lavoisier de Versailles, UMR CNRS 8180, University of Versailles St-Quentin en Yvelines, Versailles, 78035, France.
Summary
Constrained alpha-amino acid residues like (αMe)Aze influence peptide structure. This study explores heterochiral peptides, revealing they adopt type-II β-turns or γ-turns based on conditions.
Area of Science:
- Peptide chemistry and structural biology.
- Organic chemistry and conformational analysis.
Background:
- Constrained alpha-amino acid residues significantly influence peptide backbone 3D structure.
- Nα-alkylated four-membered ring and Cα-methylation characterize (αMe)Aze, an intriguing constrained residue.
- Previous work showed homochiral -(S)-(αMe)Aze-(S)-Ala- peptides form unique γ-bend ribbons.
Purpose of the Study:
- To investigate the 3D structure of heterochiral peptides containing (S)-Ala and (R)-(αMe)Aze.
- To analyze peptide conformational preferences from dimer to hexamer length.
- To understand how sequence chirality affects peptide folding.
Main Methods:
- Synthesis of sequential peptides from dimer to hexamer length.
- Three-dimensional structural analysis using various experimental techniques.
- Conformational analysis of peptide backbone structures.
Main Results:
- Heterochiral peptides containing (S)-Ala/(R)-(αMe)Aze exhibit diverse folding patterns.
- Peptides were observed to adopt either type-II β-turns or γ-turns.
- Conformation is dependent on specific experimental conditions.
Conclusions:
- The incorporation of (R)-(αMe)Aze into heterochiral peptide sequences allows for tunable conformational outcomes.
- (S)-Ala/(R)-(αMe)Aze peptides can be engineered to form either type-II β-turns or γ-turns.
- This provides a novel strategy for designing peptides with specific secondary structures.
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