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Updated: Jul 8, 2026
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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Intermolecular packing and alignment in an ordered beta-hairpin antimicrobial peptide aggregate from 2D solid-state
Ming Tang1, Alan J Waring, Mei Hong
1Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
Journal of the American Chemical Society
|October 6, 2005
Summary
Solid-state aggregation reveals how the antimicrobial peptide protegrin-1 (PG-1) forms ordered structures. These findings explain PG-1
Area of Science:
- Biophysics
- Structural Biology
- Antimicrobial Peptides
Background:
- Antimicrobial peptides (AMPs) are crucial for innate immunity.
- Understanding the aggregation and structure of AMPs like protegrin-1 (PG-1) is key to their function.
- The solid-state behavior of PG-1 can provide insights into its membrane interactions.
Purpose of the Study:
- To investigate the aggregation and packing of protegrin-1 (PG-1) in the solid state.
- To elucidate the oligomerization and hydrogen-bonding propensity of PG-1.
- To correlate solid-state structure with PG-1's behavior in lipid bilayers.
Main Methods:
- Incubation of PG-1 in phosphate-buffered saline to form aggregates.
- Solid-state Nuclear Magnetic Resonance (NMR) spectroscopy (13C, 15N, 1H spin diffusion).
- Electron microscopy (EM).
Main Results:
- Well-ordered, nanometer-scale PG-1 aggregates were formed in solution.
- Solid-state NMR and EM confirmed parallel orientation of beta-hairpin molecules in ordered aggregates, with like strands at the interface.
- Disordered and lyophilized samples showed random packing (parallel and antiparallel), unlike ordered aggregates.
Conclusions:
- Solid-state aggregation of PG-1 reveals specific intermolecular packing consistent with oligomerization in lipid bilayers.
- The study demonstrates the utility of solid-state aggregation for determining peptide quaternary structure.
- This approach offers valuable insights into the oligomerization mechanisms of AMPs in biological membranes.
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