Terminal-Directed Supramolecular Liquid Crystal Formation by Designed Coiled-Coil Interparticle Stacking

Area of Science:

• Biomolecular Engineering
• Materials Science
• Supramolecular Chemistry

Background:

• Understanding peptide self-assembly is crucial for designing advanced materials.
• Controlling hierarchical structures from sequence-level information is a significant challenge.

Purpose of the Study:

• To demonstrate a simulation-guided framework for designing peptides with predictable liquid crystalline behavior.
• To investigate the role of terminal residue interactions in peptide self-assembly and phase formation.

Main Methods:

• Computational design of single charge-type (SC) coiled-coil peptides.
• Experimental characterization of lyotropic liquid-crystalline (LC) phases.
• Analysis of peptide concentration, salt effects, and terminal residue interactions.

Main Results:

• SC coiled-coil peptides self-assemble into multiple LC phases (nematic, hexagonal columnar, smectic A, smectic B) via end-to-end stacking.
• Terminal residue interactions (N-terminus flexibility, C-terminus attraction) dictate stacking and critical LC-forming concentration (CLC).
• Tryptophan-mediated cross-linking enhanced the mechanical properties of the peptide liquid crystal.

Conclusions:

• Peptide sequence-level design can predictably control macroscopic liquid crystal phase behavior.
• End-to-end stacking of coiled-coil peptides offers a versatile strategy for de novo material design.
• This approach provides a blueprint for engineering peptide-based materials with tailored properties.