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Updated: Jan 25, 2026
10:12
Construction of Cyclic Cell-Penetrating Peptides for Enhanced Penetration of Biological Barriers
Published on: September 19, 2022
2.8K
Solvent-Enhanced Conformational Flexibility of Cyclic Tetrapeptides
Nadja Berger1, Laura J B Wollny2, Pandian Sokkar2,3
1Organische Chemie II, Ruhr-University of Bochum, Universitätsstr. 150, 44780, Bochum, Germany.
Summary
Solvent and temperature significantly alter cyclic peptide structures. D-1 peptide conformation changes with temperature in CHCl3, unlike its diastereomer L-1 or when in CH3CN, due to flexibility.
Area of Science:
- Chemical Physics
- Molecular Biophysics
- Organic Chemistry
Background:
- Solvent and temperature critically influence cyclic peptide structural properties by modulating molecular flexibility.
- Understanding these environmental effects is key to controlling peptide conformation for various applications.
Purpose of the Study:
- To investigate the impact of solvent and temperature on the conformational behavior of two cyclic peptides, D-1 and its diastereomer L-1.
- To elucidate the molecular mechanisms underlying observed conformational changes using computational methods.
Main Methods:
- Temperature-dependent Nuclear Magnetic Resonance (NMR) spectroscopy.
- Fourier-Transform Infrared (FT-IR) spectroscopy.
- Replica Exchange Molecular Dynamics (REMD) simulations and Quantum Mechanics/Molecular Mechanics (QM/MM) calculations.
Main Results:
- A significant temperature-dependent conformational change was observed for D-1 in chloroform (CHCl3), but not in acetonitrile (CH3CN).
- The diastereomer L-1 exhibited minimal conformational changes across the tested temperature ranges and solvents.
- Computational analyses attributed the heightened temperature sensitivity of D-1 in CHCl3 to increased intramolecular hydrogen bonding and flexibility.
Conclusions:
- Environmental factors, specifically solvent and temperature, play a crucial role in dictating the conformational landscape of cyclic peptides.
- The observed differences in temperature response between D-1 and L-1 highlight the stereospecific sensitivity of cyclic peptide structures to their surroundings.
- This study offers valuable insights into the structure-property relationships of cyclic peptides, essential for their rational design and application.
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