@article{21749,
  abstract     = {The collagen triple helix assembles hierarchically into bundled oligomers, solvated networks, and fibers. Synthetic peptide assemblies, driven by supramolecular interactions, can form single triple helices through intrahelical amino acid pairs; however, the principles guiding interhelical associations into higher-order structures remain unclear. Here, we incorporate cation−π and electrostatic charge pairs to probe interhelical interactions and elucidate the mechanisms driving triple helix assembly into fibrils, nanotubes, and nanosheets. Introducing cation−π pairs into a fibrillating collagen mimetic resulted in D-periodic fibrils with pH-sensitive gelation. By alternating the presentation of electrostatic and cation−π pairs, the assembly of another D-periodic fibril featuring inner and outer triple-helical layers was resolved by cryo electron microscopy to a resolution of 8 Å. At physiological pH, antiparallel association of these triple helices leads to the formation of nanotubes. The packing behavior of triple helices correlates with the interhelical interactions, where parallel associations favor fibril formation and antiparallel interactions drive nanotube and nanosheet assembly. These self-assembling triple-helical peptides demonstrate how packing of higher-order structures can be tailored with supramolecular interactions and establish the relationship of different hierarchical collagen-mimetic assemblies as pH-dependent.},
  author       = {Cole, Carson C. and Kreutzberger, Mark A.B. and Klein, Kevin and Cahue, Kiana A. and Pogostin, Brett H. and Farsheed, Adam C. and Swain, Joseph W.R. and Bui, Thi H. and Dey, Arghadip and Makhoul, Jonathan T. and Dubackic, Marija and Pal, Antara and Olsson, Ulf and Šarić, Anđela and Egelman, Edward H. and Hartgerink, Jeffrey D.},
  issn         = {1526-4602},
  journal      = {Biomacromolecules},
  number       = {4},
  pages        = {2956--2965},
  publisher    = {American Chemical Society},
  title        = {{Supramolecular assembly of collagen-mimetic eptide D-periodic fibrils and nanoassemblies}},
  doi          = {10.1021/acs.biomac.6c00345},
  volume       = {27},
  year         = {2026},
}

@article{18168,
  abstract     = {Despite the considerable interest in the recombinant production of synthetic spider silk fibers that possess mechanical properties similar to those of native spider silks, such as the cost-effectiveness, tunability, and scalability realization, is still lacking. To address this long-standing challenge, we have constructed an artificial spider silk gene using Golden Gate assembly for the recombinant bacterial production of dragline-mimicking silk, incorporating all the essential components: the N-terminal domain, a 33-residue-long major-ampullate-spidroin-inspired segment repeated 16 times, and the C-terminal domain (N16C). This designed silk-like protein was successfully expressed in Escherichia coli, purified, and cast into films from formic acid. We produced uniformly 13C–15N-labeled N16C films and employed solid-state magic-angle spinning nuclear magnetic resonance (NMR) for characterization. Thus, we could demonstrate that our bioengineered silk-like protein self-assembles into a film where, when hydrated, the solvent-exposed layer of the rigid, β-nanocrystalline polyalanine core undergoes a transition to an α-helical structure, gaining mobility to the extent that it fully dissolves in water and transforms into a highly dynamic random coil. This hydration-induced behavior induces chain dynamics in the glycine-rich amorphous soft segments on the microsecond time scale, contributing to the elasticity of the solid material. Our findings not only reveal the presence of structurally and dynamically distinct segments within the film’s superstructure but also highlight the complexity of the self-organization responsible for the exceptional mechanical properties observed in proteins that mimic dragline silk.},
  author       = {Wu, Dongqing and Koscic, Anamaria and Schneider, Sonja and Dubini, Romeo C. A. and Rodriguez Camargo, Diana C. and Schneider, Sabine and Rovo, Petra},
  issn         = {1526-4602},
  journal      = {Biomacromolecules},
  number       = {3},
  pages        = {1759--1774},
  publisher    = {American Chemical Society},
  title        = {{Unveiling the dynamic self-assembly of a recombinant dragline-silk-mimicking protein}},
  doi          = {10.1021/acs.biomac.3c01239},
  volume       = {25},
  year         = {2024},
}