Bioengineered Protein Fibers with Anti‐Freezing Mechanical Behaviors

Abstract

Most biological protein fibers exhibit extraordinary mechanical performance at room temperatures but inferior freezing resistance. Maintaining fiber's high strength and toughness under subzero conditions remains a great challenge. Herein, a class of freezing tolerant protein fibers is reported with favorable ice-phobic capacity and cryogenic mechanical performance by genetic engineering. Inspired by nature, chimeric recombinant proteins consist of highly ordered structural protein domains and antifreeze protein (AFP) modules, showing excellent ice recrystallization inhibition activity. Such features endow the resulting protein fibers with remarkable mechanical properties and good mechanical stability in subzero environments. In stark contrast to conventional fibers, the engineered protein fibers maintain high cryogenic stiffness and toughness even at −20 and −40 °C. The synergistic contribution of structural protein and AFP plays an important role for the extraordinary anti-freezing mechanical behaviors. Thus, this study pioneers an engineering approach for the next generation of biological fibers with tailored applications in extreme settings.

Biomimetic Structural Proteins: Modular Assembly and High Mechanical Performance

“…These fibers exhibiting ice recrystallization inhibition showed superior stiffness and toughness compared to those without AFP modules, even at −20 and −40 °C. 31 During the modular assembly process, inducing molecules including glutaraldehyde (GA), crown ethers, 32 surfactants, 2,33,34 and DNA 3 are introduced to induce multiple interactions and molecular cross-linking networks, facilitating the assembly of the biomimetic structural proteins into macroscopic fibers with high mechanical properties. Free lysine residues in proteins provide unique sites for cross-linking.…”

“…We designed SRT-AFP structural proteins. These fibers exhibiting ice recrystallization inhibition showed superior stiffness and toughness compared to those without AFP modules, even at −20 and −40 °C …”

Engineered Bicomponent Adhesives with Instantaneous and Superior Adhesion Performance for Wound Sealing and Healing Applications

“…[22,23] The design of structural proteins through protein molecular engineering could precisely manipulate their physical and biological properties, which is imperative to develop robust bioadhesives with a simple and convenient method. [17,[24][25][26][27][28] Tailored structures and functional motifs in engineered proteins modulate the interactions within bioadhesives, contributing to strong adhesion performances under complex physiological environments. [29][30][31][32] Furthermore, engineered proteins can be produced at the industrial level through microbial fermentation engineering, enabling large-scale production of bioadhesives at a relatively low cost.…”

Biosynthesis, Assembly, and Biomedical Applications of High-Performance Engineered Proteins

“…Structural proteins, such as spidroin, elastin, and collagen, which have excellent mechanical properties, biocompatibility, and degradability, are a class of biopolymers produced by natural evolution. Their unique modular sequences endow these proteins with precise structural and functional controllability lacking in many synthetic polymers. , More importantly, the self-assembly properties of high-performance structural proteins allow them to assemble into hierarchical material systems, including fibers, adhesives, micelles, nanocarriers, phase separation microstructures, framework systems, etc. − High-performance structural protein-based materials exhibit broad applications in high-tech fields from wearable devices and biomedicine to military scenarios. − The growing demand for protein-based biomaterials has increased interest in various protein engineering strategies.…”