Conformation-driven strategy for resilient and functional protein materials

Abstract

The exceptional elastic resilience of some protein materials underlies essential biomechanical functions with broad interest in biomedical fields. However, molecular design of elastic resilience is restricted to amino acid sequences of a handful of naturally occurring resilient proteins such as resilin and elastin. Here, we exploit non-resilin/elastin sequences that adopt kinetically stabilized, random coil–dominated conformations to achieve near-perfect resilience comparable with that of resilin and elastin. We also show a direct correlation between resilience and Raman-characterized protein conformations. Furthermore, we demonstrate that metastable conformation of proteins enables the construction of mechanically graded protein materials that exhibit spatially controlled conformations and resilience. These results offer insights into molecular mechanisms of protein elastomers and outline a general conformation-driven strategy for developing resilient and functional protein materials.

Acetic Acid Enables Precise Tailoring of the Mechanical Behavior of Protein-Based Hydrogels

“…Peptide- and nonglobular-based hydrogels have attracted broad interest in biomedical applications and research. Several studies tried to utilize the intramolecular interactions of peptide chains and the precise engineering of α-helix and β-sheet structures to control and improve the mechanical and microstructure properties of peptide-based hydrogels. − In addition, synthetic proteinaceous hydrogels constructed from nonglobular proteins such as elastin have been extensively investigated to fine-tune their mechanical and structural behavior. − On the contrary, globular protein-based networks exhibit an inherently viscoelastic behavior with precise relaxation times, stretchability, and functionality resulting from the folding transitions of protein domains at the nanoscale level within the hydrogel matrix. ,,, The protein (un)­folding nanomechanics were used to engineer hydrogels with shape-memory , and morphing capabilities. Additionally, protein engineering technologies were implemented to design tandem polyprotein structures to form muscle-like biomaterials , and self-healing protein hydrogels. , Moreover, protein biochemical diversity and its interactions with polymers and cations have been explored to precisely tailor the mechanical behavior of hydrogel samples. , …”

Down-Regulating Scar Formation by Microneedles Directly via a Mechanical Communication Pathway

“…42 Increasing the β-sheet content yields silk materials with lower degradation and solubility, but higher crystallinity and breaking strength. 36,37,43,44 Postprocessed by methanol vapor annealing overnight, the SF MNs reached a much higher content of βsheet secondary structure than primary SF, which was confirmed using the Fourier-transform infrared spectroscopy (FTIR) method. The peak devolution of the amide I region was performed using a secondary derivative method in Peakfit software.…”

“…In order to achieve efficient penetration into the scar tissue and physical interaction, the primary silk microneedles were further modified by methanol vapor annealing to promote the secondary structure of SF molecules transformed from the random coil to β-sheet conformation . Increasing the β-sheet content yields silk materials with lower degradation and solubility, but higher crystallinity and breaking strength. ,,, Postprocessed by methanol vapor annealing overnight, the SF MNs reached a much higher content of β-sheet secondary structure than primary SF, which was confirmed using the Fourier-transform infrared spectroscopy (FTIR) method. The peak devolution of the amide I region was performed using a secondary derivative method in Peakfit software.…”

“…To test our hypothesis, we studied the efficacy and mechanism of polymeric microneedles to remodel hypertrophic scars and explored the mechanism of underlying mechanotransduction. We used silk fibroin, a natural material with tunable stiffness and strength, , for the fabrication of MN patches. Scar elevation index, tissue stiffness, ultimate tensile strength, and ECM ultrastructure were investigated.…”

What Is the Force-per-Molecule Inside a Biomaterial Having Randomly Oriented Units?

“…16 This approach has been used for both globular and fibrillar proteins. 17 Other methods of synthesizing protein-based materials, which rely on different cross-linking chemistries, have also great potential. For example, glutaraldehyde based cross-linking was shown to produce protein materials with higher cross-linking density, 18 while streptavidin−biotin or Spytag-Spycatcher interactions were successfully used to produce materials with better controlled cross-linking geometries.…”