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Updated: Jul 13, 2026
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Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides
Published on: November 21, 2013
Peptides with regular enantiomeric sequences: a wide class of modular self-assembling architectures
Pasquale De Santis1, Stefano Morosetti, Anita Scipioni
1Dipartimento di Chimica, Università di Roma La Sapienza, P.le A.Moro 5 1-00185, Italy.
Journal of Nanoscience and Nanotechnology
|August 1, 2007
Summary
Organic nanotubes self-assemble from cyclic peptides with alternating D- and L-amino acids, forming hydrogen-bonded structures. These structures show potential as ion channels, with experimental evidence of single-molecule conducting events.
Area of Science:
- Supramolecular Chemistry
- Nanotechnology
- Organic Chemistry
Background:
- Organic trans-annular assemblies are crucial for nanotechnological devices.
- Alternating enantiomeric amino acid sequences in cyclic peptides facilitate self-assembly.
- Conformational equivalence drives the formation of hydrogen-bonded, trans-annular architectures.
Purpose of the Study:
- To synthesize and characterize alternating polypeptide structures.
- To investigate their self-assembly and ion-channel properties.
- To explore strategies for creating advanced nanotechnological constructs.
Main Methods:
- Synthesis of alternating linear and cyclic polypeptides.
- Conformational analysis using Nuclear Magnetic Resonance (NMR) and Circular Dichroism (CD) spectroscopy.
- Investigation of self-assembly in solution and ion-channel activity across bilayer membranes.
Main Results:
- Experimental confirmation of self-assembling trans-annular architectures.
- Demonstration of ion-channel behavior with evidence of single-molecule conducting events.
- Successful bridging of cyclic DL-lysine side chains using metal chelates for construct stabilization.
Conclusions:
- Alternating enantiomeric amino acid sequences are effective for designing self-assembling organic nanotubes.
- These structures exhibit promising ion-channel capabilities for nanotechnological applications.
- Chemically bridged structures offer a pathway to complex, functional nanomaterials.
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