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Updated: Nov 6, 2025

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Published on: September 17, 2017

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Nuclear magnetic resonance studies on conformation and stability of mastoparan in methanol

Yoshinori Miura1

  • 1Center for Advanced Instrumental Analysis, Kyushu University, Kasuga, Japan.

Journal of Peptide Science : an Official Publication of the European Peptide Society
|May 11, 2021
PubMed

Insights

Mastoparan (MP), a wasp venom peptide, forms a stable helix in methanol, mimicking cell membranes. This helical structure remains intact at high temperatures, crucial for its biological function.

Area of Science:

  • Biochemistry
  • Structural Biology
  • Biophysics

Background:

  • Mastoparan (MP) is a 14-amino acid peptide from wasp venom.
  • MP penetrates cell membranes and activates G proteins, leading to histamine release.

Purpose of the Study:

  • Investigate the conformation and thermal stability of Vespula lewisi mastoparan (MP) in methanol.
  • Assess methanol as a membrane mimetic for MP.

Main Methods:

  • Proton nuclear magnetic resonance (NMR) spectroscopy.
  • Analysis of NOESY cross peaks, spin-spin coupling constants, NH chemical shifts, and temperature-dependent NMR signal intensity.

Main Results:

  • MP forms an α-helical structure between residues 5 and 12 at low temperatures.
  • The helical conformation is maintained up to 54°C.
  • Methanol effectively mimics the membrane environment for MP.

Conclusions:

  • The stable helical conformation of MP in methanol is relevant to its function as a venom peptide.
  • Methanol is a suitable membrane mimetic for studying MP's interactions.
Keywords:
NMRhelical conformationintramolecular hydrogen bondmastoparanthermal stability

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