Genetically engineered materials: Proteins and beyond

Abstract

Information-rich molecules provide opportunities for evolution. Genetically engineered materials are superior in that their properties are coded within genetic sequences and could be fine-tuned. In this review, we elaborate the concept of genetically engineered materials (GEMs) using examples ranging from engineered protein materials to engineered living materials. Protein-based materials are the materials of choice by nature. Recent progress in protein engineering has led to opportunities to tune their sequences for optimal material performance. Proteins also play a central role in living materials where they act in concert with other biological components as well as nonbiological cofactors, giving rise to living features. While the existing GEMs are often limited to those constructed by building blocks of biological origin, being genetically engineerable does not preclude nonbiologic or synthetic materials, the latter of which have yet to be fully explored.

Catcher/Tag Toolbox: Biomolecular Click‐Reactions For Protein Engineering Beyond Genetics

“…Protein-based hydrogels are promising alternatives to hydrogels made from synthetic polymers owing to their biocompatibility, biodegradability, and the potential to incorporate bioactive motifs or functional groups. [87] Protein-based hydrogels are widely used in various biomedical applications, such as tissue engineering and regeneration medicine. These hydrogels are usually constructed by physical cross-linking, chemical crosslinking, or a combination of the two.…”

“…Catcher/Tag pairs, occupy a large proportion in the protein copolymers and thus result in low cross-linking density and poor mechanical performance of the final hydrogel. [87] To minimize the impact of this scar, three strategies have been applied to reduce the molecular weight of the Catcher/Tag pairs. One approach is to split a CnaB domain into three fragments, as in the case of Type C/N (Table 1, Figure 1F).…”

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.…”

“…Their unique modular sequences endow these proteins with precise structural and functional controllability lacking in many synthetic polymers. 1,2 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. 3−11 High-performance structural protein-based materials exhibit broad applications in high-tech fields from wearable devices and biomedicine to military scenarios.…”

Orchestrating Chemical and Physical Cross-Linking in Protein Hydrogels to Regulate Embryonic Stem Cell Growth

“…They are usually made from synthetic polymers, peptides, proteins, polysaccharides, etc. − Among them, proteins are particularly attractive since they can act as both structural scaffolds and biological cues. Moreover, protein properties are encoded by genes and can be precisely varied by recombinant protein technology, providing an ideal platform to address the above problems. − While most chemical cross-linking relies on reactive functional groups (e.g., amines and thiols) on protein, genetically encoded click chemistry (such as split-intein-mediated ligation and SpyTag/SpyCatcher reaction) can also be applied. Noncovalent protein–protein interactions (such as helix-bundle association and TIP-1/Kir complexation) are often utilized as physical cross-linking to bring in viscoelastic properties which may be precisely varied by single site mutation.…”