Design of novel enzymes with the incorporation of noncanonical amino acids

Enzymes are highly efficient biocatalysts known for their chemical, regio-, and stereoselectivity, making them valuable in industrial applications. While directed evolution has expanded the scope of enzyme-catalyzed reactions, the range of enzymatic reactions remains limited compared to reactions catalyzed by chemical catalysts. Computational enzyme design has achieved <i>de novo</i> enzyme design, but the approach is often complex, time-intensive, and has a low success rate. A promising strategy to design novel enzymes involves developing noncanonical amino acids (ncAAs) with catalytic potential and integrating them into protein scaffolds <i>via</i> genetic codon expansion technology. This method combines the novel reactivity of ncAAs with the high selectivity provided by protein scaffolds, significantly enhancing the diversity of enzyme-catalyzed reactions. This review discusses recent advancements in novel enzyme design using ncAAs, including those being used as catalytic groups, metal-coordinating groups, heme ligands, and photocatalytic groups. The article emphasizes the broad potential of using ncAAs in enzyme design to expand the diversity of enzyme-catalyzed reactions, and outlooks the potential applications of artificial intelligence technology in this area.